TREATMENT OF PANCREATIC PSEUDOCYSTS Å. Andrén-Sandberg , C. Ansorge , K. Eiriksson
Transcription
TREATMENT OF PANCREATIC PSEUDOCYSTS Å. Andrén-Sandberg , C. Ansorge , K. Eiriksson
Scandinavian Journal of Surgery 94: 165–175, 2005 TREATMENT OF PANCREATIC PSEUDOCYSTS Å. Andrén-Sandberg1, C. Ansorge1, K. Eiriksson1, T. Glomsaker1, A. Maleckas2 1 2 Department of Surgery, Stavanger University Hospital, Stavanger, Norway Department of Surgery, Kaunas Medical University Hospital, Kaunas, Lithuania ABSTRACT According to the Atlanta classification an acute pseudocyst is a collection of pancreatic juice enclosed by a wall of fibrous or granulation tissue, which arises as a consequence of acute pancreatitis or pancreatic trauma, whereas a chronic pseudocyst is a collection of pancreatic juice enclosed by a wall of fibrous or granulation tissue, which arises as a consequence of chronic pancreatitis and lack an antecedent episode of acute pancreatitis. It is generally agreed that acute and chronic pseudocysts have a different natural history, though many reports do not differentiate between pseudocysts that complicate acute pancreatitis and those that complicate chronic disease. Observation – “conservative treatment” – of a patient with a pseudocyst is preponderantly based on the knowledge that spontaneous resolution can occur. It must, however, be admitted that there is substantial risk of complications or even death; first of all due to bleeding. There are no randomized studies for the management protocols for pancreatic pseudocysts. Therefore, today we have to rely on best clinical practice, but still certain advice may be given. First of all it is important to differentiate acute from chronic pseudocysts for management, but at the same time not miss cystic neoplasias. Conservative treatment should always be considered the first option (pseudocysts should not be treated just because they are there). However, if intervention is needed, a procedure that is well known should always be considered first. The results of percutaneous or endoscopic drainage are probably more dependent on the experience of the interventionist than the choice of procedure and if surgery is needed, an intern anastomosis can hold sutures not until several weeks (if possible 6 weeks). Key words: Pancreatic pseudocyst; acute pancreatitis; chronic pancreatitis; treatment Pseudocysts are localised collections of fluid from the pancreatic gland surrounded by nonepithelialised granulation tissue. The fluid collection follows an insult to the pancreas. Pancreatic pseudocysts are not common, and rarely does a single surgeon acquire a Correspondence: Åke Andrén-Sandberg, M.D. Department of Surgery Stavanger University Hospital NO - 4068 Stavanger Norway Email: saak@sir.no large experience concerning their management. The pathogenesis of the pseudocysts has earlier been rather superficially described and the epidemiology and natural history have most often been studied in a limited way. However, the development of diagnostic ultrasound and computed tomography, CT, has changed this drastically. An increased frequency of cystic pancreatic lesions are on the same time seen today – probably not due to an increased incidence totally, but an increased incidence of symptom-poor lesions. This has given new knowledge and an improved interest for research on the disease, and means that the previous knowledge of pancreatic pseudocysts only refers to those giving symptoms. 166 Å. Andrén-Sandberg, C. Ansorge, K. Eiriksson, T. Glomsaker, A. Maleckas Previously clinical examination, laparotomy, barium studies and angiography only detected cysts big enough to cause morphologic abnormalities in adjacent viscera. Now we also see small and asymptomatic pseudocysts. However, with more pseudocysts discovered we have to evidence-based answer the basic questions on optimal diagnostics and treatment – or no treatment at all – in all these cases. Not many years ago the management of pancreatic pseudocysts was thought to be relatively simple: internal drainage. The major controversy was whether to intervene surgically early – which might result in an unwanted external drainage – or to wait until maturation of the wall of the pseudocyst, i.e. when the wall could hold sutures. However, technological advances such as percutaneous and endoscopic drainage technique have made treatment of pancreatic pseudocysts more complex. Now the Atlanta classification system has provided us with the required definitions, but still they are not always used (1). CLASSIFICATION There is a certain confusion in the literature on the terms “acute” and “chronic” with regard to pseudocysts. According to the Atlanta classification (1) an acute pseudocyst is a collection of pancreatic juice enclosed by a wall of fibrous or granulation tissue, which arises as a consequence of acute pancreatitis or pancreatic trauma, whereas a chronic pseudocyst is a collection of pancreatic juice enclosed by a wall of fibrous or granulation tissue, which arises as a consequence of chronic pancreatitis and lack an antecedent episode of acute pancreatitis. This means that the terms acute and chronic regarding pseudocysts is used otherwise in some respects than how these words are used in other medical conditions. Sometimes classification of the pseudocysts into acute and chronic types is – unfortunately – based on the time interval (usually 4–6 weeks from the acute attack) in an attempt to help decide the timing of surgical intervention and in these cases does not take the underlying disease into account. With this use of the term acute pseudocysts occur in acute pancreatitis but can develop also in chronic pancreatitis after an acute exacerbation. On the other hand, chronic pseudocysts are usually associated with chronic pancreatitis but may develop after an episode of acute pancreatitis as well (2). The situation is somehow confusing and some attempts have been made to set it clear by classifying pseudocysts according to pathological changes underlying acute or chronic pancreatitis. As early as 1961 Sarles and colleagues (3, 4) proposed a classification of pancreatic pseudocysts depending on whether they were associated with acute or chronic pancreatitis. Pseudocysts associated with acute pancreatitis were called necrotic pseudocysts because they resulted from pancreatic necrosis and extravasation of pancreatic juice. Based on pathological studies pseudocysts originating from chronic pancreatitis were called retention pseudocysts. Pathological examinations revealed that intrapancreatic fluid collections associated with chronic pancreatitis sometimes were true cysts caused by dilation of pancreatic ducts behind calculi, plugs, or strictures. Extrapancreatic pseudocysts complicating chronic pancreatitis were more frequently caused by a rupture of these pseudocysts into peripancreatic tissues (retention pseudocysts) rather than by acute necrotic pancreatitis complicating the chronic lesion (5). There are no absolute borders between acute and chronic pseudocysts, but in the obvious cases there are clear differences (Table 1). NATURAL HISTORY The widespread application of ultrasonography and CT has advanced our knowledge of the natural history of pancreatic pseudocysts. It is generally agreed that acute and chronic pseudocysts have a different natural history, though many reports do not differentiate between pseudocysts that complicate acute pancreatitis and those that complicate chronic disease. There are few, if any at all, reliable data on the mechanisms of spontaneous resolution of pancreatic pseudocysts. The only documented way is spontaneous rupture of a pancreatic pseudocyst into the adjacent organs (6, 7). Factors found to reduce the likelihood of spontaneous resolution of cystic lesions are multiple cysts (8), pseudocyst location in the tail of the pancreas (9), thicker pseudocyst wall (10, 11), a communication with the pancreatic duct with an associated proximal stricture of the pancreatic duct (11), increase in size on follow-up examination (8), biliary or postopera- TABLE 1 Typical differences between acute and chronic pseudocysts Acute pseudocysts Chronic pseudocysts First notice acute (after a bout of acute pancreatitis) during investigation of long-standing pain Number of pseudocysts seldom more than one often multiple Size may be large, seldom small seldom large Changing size may be changing rather quickly slow changes in both directions Intra/extrapancreatic may be any or combined always intrapancreatic Treatment of pancreatic pseudocysts tive etiology of pancreatitis (12), and extrapancreatic development in chronic alcoholic pancreatitis (13). Severity of acute pancreatitis as well as extent of pancreatic necrosis was found to influence spontaneous resolution rate. In Neoptolemos’ and colleagues’ study all pseudocysts resolved spontaneously if they resulted after mild acute pancreatitis or severe pancreatitis with less than 25 percent of pancreas necrosis (14). ACUTE PSEUDOCYSTS Earlier studies suggest that spontaneous resolution of an acute pseudocyst occurred in from 8 and up to 70 percent of patients (15-20). The more patients with diagnosed acute pseudocyst will actually have acute fluid collections the higher resolution rate will be. The situation has not changed even with the advent of ultrasonography as there in these reports most often has not been precise definition of the pseudocyst. Therefore, the possibility that the results of resolution of acute fluid collections and acute pseudocysts were presented together should be encountered. From a clinical point of view it is of course of interest if there are prognostic factors can give at least a hint of which pseudocysts are probable to regress – and which will not resolve. Warshaw and Rattner (10) reported that no cyst that presented more than 6 weeks following an attack of acute pancreatitis resolved. On the other hand, the authors noted that the size of the cyst did not seem to affect the chance of resolution. Similarly, Bradley and colleagues followed the natural history of pseudocysts in 93 patients, 31 of who had acute pancreatitis and 62 had chronic disease. Spontaneous resolution occurred in ten (42 %) of 24 patients in whom a pseudocyst was present for more than 6 weeks. By contrast, of 13 pseudocysts that had been present for 7– 12 weeks, only one (8 %) resolved spontaneously. Spontaneous resolution did not occur in any of the remaining 12 patients followed for up to 18 weeks. The clear implication was that pseudocysts still present at 6 weeks are unlikely to resolve spontaneously (20). This conclusion was challenged by the results of more recent studies. In Vitas’ and Sarr’s (21) series of 68 patients treated with expectant approach overall resolution of the pseudocyst occurred in 57 percent of the 24 patients with satisfactory radiographic follow-up, and 38 percent resolved more than 6 months after diagnosis. O’Malley and colleagues (22) noted that pseudocysts of more than 4 cm resolved spontaneously at a mean of 3 months after diagnosis, although in one case resolution did not occur until 28 months. Maringhini and colleagues (9) found that within one year after diagnosis 65 percent of acute pseudocysts resolved. CHRONIC PSEUDOCYSTS Aranha and colleagues (8) noted that patients with pancreatic calcifications and evidence of chronic pancreatitis had no resolution of their pancreatic pseudocyst. Warshaw and Rattner (10) from their series 167 of 42 patients with pancreatic pseudocysts also concluded that evidence of chronic pancreatitis and pancreatic duct abnormality other than communication with the pseudocyst were criteria suggesting that a pseudocyst will not resolve spontaneously. Gouyon and colleagues observed pseudocyst resolution rate of 26 percent in patients with chronic alcoholic pancreatitis. The median time to regression was 29 weeks (range 2–143) and independent predictive factor of pseudocyst resolution or asymptomatic course was size less than 4 cm (13). McConnell and colleagues (17) reported resolution rate in only 3 percent of cases with chronic pancreatic pseudocysts. Bourliere and Sarles reviewed 77 consecutive patients with pseudocysts of the pancreas associated with chronic pancreatitis. Ultrasonography and/or CT scans showed that 9 percent of them resolved spontaneously. The main diameter of chronic pancreatic pseudocysts that resolved was 3 cm (5). RISK FOR COMPLICATIONS IN UNTREATED PANCREATIC PSEUDOCYSTS Observation – “conservative treatment” – of a patient with a pseudocyst is preponderantly based on the knowledge that spontaneous resolution can occur. The doctor who is very enthusiastic about observation, however, must admit that there is substantial risk of complications or even death. In Bradley’s and colleagues’ series the incidence of complications correlated directly with the length of time the pseudocyst was present: 20 percent of patients with early pseudocyst (< 6 weeks) had a complication, as opposed to 46 percent with cysts that were 7–12 weeks old and 75 percent of those with chronic cysts (beyond 13 weeks). Of particular interest is the observation that each of the seven deaths (12 %) occurred as a direct result of the pseudocyst and that their complications developed an average of thirteen and a half weeks after the presumed initial development of the pseudocyst (20). More recently, Yeo and colleagues in Baltimore, used serial CT to observe the natural history of pancreatic pseudocysts in 75 patients; their findings challenge the conclusion of Bradley and colleagues that delay is at best fruitless and at worst hazardous. Thirty-six patients who were asymptomatic were managed without operation and were observed for a mean of 1 year. Of these, 60 percent had complete resolution of the pseudocyst and 40 percent had pseudocysts that remained stable or reduced in size. Only one patient of the 36 treated expectantly, i.e. without operation, developed a complication from the pseudocyst in the form of a transient intracystic haemorrhage (23). Vitas and Sarr reported 68 patients initially treated selectively with a nonoperative, expectant approach. Severe, life-threatening complications in this group followed up for a mean of 46 months occurred in only 6 patients (9 %), including intracystic haemorrhage in 3, perforation in 2, and cyst infection in 1. Nineteen (28 %) patients eventually underwent elective operation directed at either the pseudocyst or other complications related to pancreatitis (21). 168 Å. Andrén-Sandberg, C. Ansorge, K. Eiriksson, T. Glomsaker, A. Maleckas Maringhini and colleagues analysed the natural history of 83 non-alcoholic patients with fluid collections and/or pseudocysts in which a chronic pancreatitis was accurately excluded. In the first six weeks of follow-up spontaneous disappearance was observed in 12 (15 %) and complications in 19 (23 %) of 83 patients. The complications observed were pain in 12 patients, infection in 4, fistula in 2, and rupture in one patient. Only two patients died. After the first six weeks of follow up, the pseudocyst spontaneously disappeared in 31 and complications occurred in 14 of 48 patients. Eleven of the patients with complications had pain, while three presented fistula (9). The cumulative experience suggests that asymptomatic pseudocysts, which remain stable or diminish in size, can be safely managed with a nonoperative approach. Close monitoring of such patients is, however, mandatory in order to detect enlarging or symptomatic pseudocysts early in their course, before occurrence of severe complications. In such cases immediate surgical intervention should be considered. THERAPY OPTIONS Currently, at least three principle forms of active therapy are available: percutaneous drainage, endoscopic drainage, and surgical interventions: excision, external drainage, and internal drainage. Surgery, which traditionally was the major treatment approach for pancreatic pseudocysts, has been challenged by the newer endoscopic techniques. Given the low complication and mortality rates and the high success rate of percutaneous and endoscopic drainage when compared with surgery, surgical intervention should be reserved only for certain cases. Addition of endoscopic ultrasonography, EUS, for endoscopic drainage is a new development and may decrease the risks associated with endoscopic drainage (24). Resolution rates after surgical and non-surgical methods are comparable, but clinical and technical aspects may mandate either method. Each patient requires an individual, multidisciplinary approach, thereby obtaining optimal treatment-outcome. PERCUTANEOUS CATHETER DRAINAGE Percutaneous catheter drainage of symptomatic pancreatic pseudocysts under computed tomography or ultrasonographic guidance is a valuable adjunct or alternative to operative pseudocyst management and has today many advocates (25–27) and is well evaluated. Insertion of a pigtail catheter allows the cyst to remain collapsed, and up to 90 percent of pseudocysts may be drained successfully in this way (28). However, long-term outcome in larger series remains to be awaited (29). Diagnostic percutaneous aspiration of peripancreatic collections is readily performed, but needle aspiration alone is generally ineffective as a therapy (except as a temporary measure) (30–32). INDICATIONS AND CONTRAINDICATIONS According to the current practice indications for percutaneous catheter drainage of pseudocysts are essentially the same as those for surgical treatment. Persistent pain, sepsis (infection), increasing size, involvement of contiguous organs or structures, and common bile duct obstruction have been accepted as indications for this procedure (33). It may be especially useful in the management of immature symptomatic pseudocyst (34) and this type of drainage can be performed in all patients, including those at highrisk (35). However, if patients are critically ill or have a high operative risk, then temporary palliation achieved with percutaneous drainage can be vital also in cases with obvious contraindications (31, 41). TIMING OF PERCUTANEOUS DRAINAGE Operation for noninfected pseudocyst generally requires 6-week delay to allow the pseudocyst wall to thicken and mature (42, 43). This delay is not essential with the percutaneous approach, which is an advantage of the latter technique. Timing is not relevant for percutaneous drainage, other than the initial interval for sequential imaging. Therefore, the only criterion for timing is clinical or imaging proof that pseudocyst does indeed require drainage, in other words, that it is symptomatic or is not resolving spontaneously (28). RESULTS OF PERCUTANEOUS ASPIRATION Percutaneous aspiration is ideal and safe for diagnosis but is usually ineffective for therapy. Especially chronic pseudocysts have thick walls and are surrounded by a fibrotic parenchyma, and needle aspiration may not be effective in collapsing the walls. TABLE 2 Contraindications to catheter drainage of pseudocysts (33, 36, 37). • collections associated with a solid or non-drainable pancreatic mass or with subtotal gland necrosis (more than 50 % parenchymal necrosis) (32, 38, 39) • suspicion of malignancy • lack of a safe access route • recent or active haemorrhage into the collection, the presence of an arterial pseudoaneurysm • collections associated with obstruction of the main pancreatic duct (especially complete cut-off) (37, 40) Treatment of pancreatic pseudocysts The pseudocysts with ductal communication, which may be in 40 percent to 70 percent of cases, reaccumulate fluid usually within 24 hours of aspiration (44). Some authors (31, 45, 46) suggest that diagnostic and therapeutic procedure in a pseudocyst that does not communicate with the pancreatic duct can be started with a fine-needle evacuation. It can have several advantages: instantaneous pain relief and clinical improvement, the risk of introducing infections by indwelling catheter is eliminated, the risk of fistula formation is negligible, and in case of recurrence, the choice between other treatment methods still remains. Furthermore, possible differential diagnoses must be kept in mind. In the case where the pseudocyst content is pus or when the cyst fluid is difficult to evacuate completely, the catheter should be inserted immediately (46). PERCUTANEOUS CATHETER DRAINAGE Henriksen and Hanke have a large reported experience – maybe the largest – of percutaneous gastropseudocystostomies with ultrasound guidance (n = 74) (47). Three quarters of their patients had chronic pancreatitis. 8.5F stent placement was successful in 92 percent of cases. In four (5 %) patients immediate complications occurred that required surgical intervention (3 cases of incorrect position of the stent and 1 bile leak into the peritoneum). Eight patients (11 %) developed sepsis and abscess formation within the cyst, shortly after stent placement. All of them had debris and cloud material at needle puncture and authors believe that this was the cause of stent occlusion and stasis that gave rise to infection. Currently they use 10F stents to facilitate better drainage. There was one (1 %) death in the series due to acute myocardial infarction. During the mean observation period of 27 months 7 patients (10 %) had pseudocyst recurrence. Furthermore, half of their patients were pain free during the follow-up period and 38 percent had improved, which means that about eight of nine were helped. The results are about similar to those achieved by surgical internal drainage in patients with chronic pancreatitis pseudocyst (48–50). From a retrospective analysis of 102 patients, Ahearne and co-workers advocated an ERCP-based algorithm for the management of pseudocysts. The algorithm focuses on pancreatic duct anatomy to assign treatment; therefore, the presence of pancreatic duct obstruction and pseudocyst communication are used to triage patients to operative management or percutaneous drainage. Percutaneous drainage was used if the main pancreatic duct was not obstructed and if no communication with the pseudocyst existed. The algorithm was evaluated by retrospectively applying it to 40 elective cases in which pre-treatment ERCPs were performed. Twenty-six treatments followed the algorithm, while 14 did not. Treatment that followed the algorithm had a significantly lower incidence of adverse outcome than those that did not (12 % vs 43 %) (51). The major complication rate varies from study to study and is in a range from 0 percent to 17 percent. 169 Haemorrhage, sepsis, pneumonia, pneumothorax, empyema, myocardial infarction, ileus, pancreatocolonic fistula, spleen injury – all have been reported (2, 25, 28, 52–54). Bacterial superinfection is of special concern (25, 28, 31, 55, 56). These patients may have clinical findings indicating infection, including fever or leukocytosis, and shall be treated with antibiotics. There are authors claiming that these infections are caused by skin contaminants, based on the high number of infections caused by resident normal flora of the skin. ENDOSCOPIC DRAINAGE The crucial anatomic fact that makes endoscopic drainage of pseudocysts feasible is that a pseudocyst does not have its own structure; rather, it is a space delineated by the normal anatomic structures adjacent to the inflammatory process – the stomach, intestine, liver, spleen, or transverse mesocolon (and part of the pancreas). The wall of the stomach or the duodenum is often common wall of the pseudocyst between which a thick inflammatory peel forms a poorly defined interface. This allows an enterostomy to be performed without concern for a potential space between the pseudocyst and the stomach and duodenum, which could develop if the pseudocyst and digestive walls were simply in close apposition (57). Endoscopic drainage of pancreatic pseudocyst appears to be a safe, effective, and definitive treatment for patients in whom anatomic considerations allow its use (58) and should therefore be understood and utilized appropriately by the surgical community (59). INDICATIONS AND BASIC PRINCIPLES Endoscopic methods for draining pseudocysts are extensions of the ERCP techniques that rely on the use of the therapeutic duodenoscope and ERCP accessories. Publications on endoscopic drainage consist primarily of case series (60–68). This cumulative experience has led to the development of certain basic principles. TABLE 3 Proposed guidelines for endoscopic pancreatic pseudocyst drainage (69). Allow pseudocyst time to mature Identify and address pseudoaneurysms Evaluate for the presence of portal hypertension and gastric varices Ensure that the pseudocyst is in close apposition to the gastric or duodenal wall Perform pancreatography first Identify debris within pseudocyst Use a transpapillary approach whenever feasible Use aspirating needle catheter to test for blood before puncture Clinical findings should be consistent with a pseudocyst 170 Å. Andrén-Sandberg, C. Ansorge, K. Eiriksson, T. Glomsaker, A. Maleckas With all drainage techniques, except percutaneous catheter drainage, it is important to allow the capsule of the pseudocyst time to ”mature”. Pseudoaneurysms can occur as a consequence of pancreatitis, and these should be carefully looked for before any puncture (70). Portal hypertension may accompany inflammatory pancreatitis, and identification of gastric varices will help avoid haemorrhage related to inadvertent puncture. Pancreatography is also important before any attempt at drainage is made (51). Whenever possible, anatomic abnormalities such as distal strictures, duct disruptions, or pancreatic duct stones should be addressed by endoscopic techniques to ensure long-term success. Two endoscopic approaches (transmural and transpapillary) can be utilised to treat pseudocysts. The choice of therapy is in part dependent on whether the cyst communicates with the pancreatic duct or is in close apposition to the gut lumen. Transpapillary drainage should be preferred, because it carries the least morbidity (60, 71–73). SHORT TERM RESULTS The endoscopic transpapillary drainage can be successfully performed in almost all cases (60, 68). Initial success, resolution of pseudocysts, was observed in 81–94 percent of cases (60, 66–68). After mean follow-up of 16–37 months were 58–83 percent of the patients free of recurrence (60, 61, 66–68). From 6 percent to 39 percent of patients required surgery (60, 66–68). The lowest overall success rate was in Smits’ and co-workers’ study; 58 percent (61) while other studies have demonstrated almost similar results. Free of pseudocyst recurrence were 75–83 percent of patients (60, 66–68). These figures perhaps can be accepted as a standard for this procedure. The (re)operation rates after endoscopic transpapillary drainage depends on various factors, not only on the recurrence of the pseudocyst. As in all cases with chronic pancreatitis, the presence or absence of chronic abdominal pain is very important. In Kozarek’s (66) study there was highest surgery rate after pseudocyst drainage; 39 percent. However, 3 of 7 patients who required surgery had it due to ongoing pain. The long-term results of this technique appear to be related in part to the initial diagnosis. The patients with acute pancreatitis and persistent duct disruptions seem to benefit from this treatment. The fluid collections resolve and in most cases they are asymptomatic on long-term follow-up. The patients with chronic pancreatitis are more likely to require surgery. Location of the pseudocysts appears to be important, as 5 of 7 F transpapillary drainage failures were associated with a pseudocyst located in the body or tail of the pancreas. Nevertheless, pseudocysts located in the tail of pancreas may also disappear after transpapillary drainage (8 cases among 12 pseudocysts located in the body or tail of the pancreas) (67). Similar results were presented in Catalano study (73). The pseudocyst drainage was successful in 60 percent of pseudocysts located in the tail of the pancre- as versus 78–86 percent when pseudocysts were located in the body or head of the pancreas (73). LONG-TERM RESULTS In a comparative study outcomes after endoscopic drainage complete endoscopic resolution was achieved in 113 of 138 patients (82 %). Resolution was significantly more frequent in patients with chronic pseudocysts (59/64, 92 %) than acute pseudocysts (23/31, 74 %) or necrosis (31/43, 72 %). Complications were also significantly more common in patients with necrosis (16/43, 37 %) than in chronic cases (11/64, 17 %) but not for those with acute pseudocysts (6/31, 19 %). At a median follow-up of 2 years after successful endoscopic treatment (resolution), pancreatic fluid collections had recurred in 18 of 113 patients (16 %). Recurrences developed more commonly in patients with necrosis (9/31, 29 %) than acute pseudocysts (2/23, 9 %) or chronic pseudocysts (7/59, 12 %). This underlines that further studies of endoscopic drainage of pancreatic fluid collections must use defined terminology to allow meaningful comparisons (74). In yet another long-term outcome study of endoscopic management of pancreatic pseudocyst there was a minimum follow-up of 2 years for a total of 38 consecutive patients. There were 27 endoscopic gastropseudocystostomies, 6 endoscopic duodenopseudocystostomies and 5 transpapillary drainages. Patients were monitored at 1 and 3 months after drainage, and finally between 24 and 80 months. Upper gastrointestinal endoscopy was done at 1 and 3 months after drainage while ultrasound was done at 3 months and at the end of follow-up. All forms of endoscopic drainage were effective in treating pancreatic pseudocyst and there was complete disappearance of the cyst within 3 months of drainage, irrespective of cause (alcohol, gallstone or trauma). Over a mean follow-up of 44 months (24–80 months) 3 patients had symptomatic recurrences while 3 had asymptomatic recurrences; all had alcohol-induced pancreatitis. No recurrences were seen in the biliary pancreatitis and trauma group. All symptomatic recurrences were successfully managed with endoscopic gastropseudocystostomy and stenting. A massive bleed in one patient required surgery while stent block and cyst infection in three patients and perforation in one patient were managed conservatively (75). SURGERY Surgery remains the standard for drainage of pseudocysts against which new methods have been compared – but this must now be seriously questioned as so few of these procedures are performed today. Surgical operations usually consist of a gastropseudocystostomy, a duodenopseudocystostomy, or a Roux-en-Y-jejunopseudocystostomy. These operative procedures carry a 10–30 percent morbidity rate, a 1–5 percent mortality rate, and a 10–20 percent rate of recurrence (76–78), thus endoscopic drainage Treatment of pancreatic pseudocysts compare favourably with this surgical ”standard” (60–68). However, the role of surgery in pancreatic pseudocysts has changed for several reasons (79). First of all endoscopic and percutaneous drainage techniques have become refined and universally available. Also, the natural history of pseudocysts has disclosed that most asymptomatic pseudocysts need no treatment. In general, the operative management of pancreatic pseudocyst aims to evacuate the pseudocyst contents and prevent serious complications. If the pseudocyst cavity is decompressed, it is likely to become obliterated with the passage of time. For acute pancreatitis there is a choice between external and internal drainage, but in chronic pancreatitis there is also a possibility of cyst resection or lateral pancreaticojejunostomy. On the other hand, pancreatic resection is appropriate in nondilated pancreatic ducts with strictures in the left part of the head, and body and tail region. The specific type of pancreatic resection depends on the exact location of the stricture. The pseudocyst is only one feature of underlying disease and the decision between resection and drainage is influenced by the extent of surrounding inflammation, vascular involvement and duct ectasia (80). Some authors have highlighted the importance of ductal stricture in planning surgical management (81, 82). Duct abnormalities present in retention pseudocyst is thought to be an indication for definitive operations such as resection of the pancreas or Puestow operation (longitudinal pancreaticojejunostomy) (2, 50, 83, 84). INDICATIONS FOR SURGERY OF PANCREATIC PSEUDOCYSTS Most surgeons would agree that an open surgical approach is usually chosen for the patients with recurrent pseudocysts, pseudocysts combined with common bile duct or duodenal stenosis, symptomatic pseudocysts associated with a dilated pancreatic duct, and those “pseudocysts” for which a diagnosis of cystic neoplasm cannot be excluded (36, 85). TIMING OF INTERVENTION The timing of intervention is a critical matter that requires considerable judgement. If operation is undertaken too early the pseudocyst wall will be friable and unable to hold sutures, necessitating external drainage with its attendant increase in morbidity and mortality rates (49, 86). However, the pseudocysts of chronic pancreatitis may be drained surgically as soon as they are diagnosed, in the confident expectation of finding a mature cyst wall capable of holding sutures. The optimal timing of intervention in acute or traumatic pseudocyst is more difficult to determine (87). Studies in dogs have shown that a period of 4–6 weeks is required for development of a mature pseudocyst wall (88). Because it is frequently impossible to date the onset of pseudocyst formation, some authors have recommended waiting 6 weeks from the time of diagnosis (49). Several authors have used a 4-week 171 waiting period with good result (89). The consensus is that a minimum of 4–6 weeks from the time of diagnosis of an acute pseudocyst is required for the wall to become sufficiently mature for safe internal drainage (20, 90). If infection or pressure symptoms demand decompression of the pseudocyst before that time, external drainage can be performed either percutaneously or at operation. EXTERNAL DRAINAGE Although frequently used in the past, external drainage has few current adherents (91). The principal disadvantages of external drainage are (85): – the potential for hemorrhage from mechanical abrasion by the drainage tube – the frequent development of secondary infection – creation of a long-term pancreatic fistula. As a result of these deficiencies, today external drainage is used principally when a misdiagnosis has been made, when the risk of anastomotic dehiscence is high because of an unanticipated infected pseudocyst, when an unexpectedly immature wall is discovered that is judged to be incapable of holding sutures, when free rupture of the pseudocyst is discovered during emergency laparotomy or after direct suture ligation of the bleeding vessel or vessels in the pseudocyst (85). INTERNAL DRAINAGE Internal drainage establishes a controlled fistula into the gastrointestinal tract and is the method of choice for all mature uncomplicated pseudocysts – if surgery is chosen. Gastropseudocystostomy and jejunopseudocystostomy are alternative procedures for establishing internal decompression (49); duodenopseudocystostomy is occasionally indicated for a small cyst in the pancreatic head (92). The mortality rate for the collected series of 1280 cases of internal drainage reported from 1969 to 1983 was 5 percent, with no significant differences between gastropseudocystostomy, jejunopseudocystostomy Roux-en-Y, or duodenopseudocystostomy (if performed by the transduodenal approach) (93). So, if open operation is considered, uncomplicated chronic pseudocysts are best drained internally into the most convenient adjacent segment of intestine (49, 94–96). CHOICE OF INTERNAL DRAINAGE PROCEDURE Controversy surrounds the question of which viscus should be used for pseudocyst drainage: stomach, duodenum or a Roux loop of jejunum. Some favour gastropseudocystostomy (95) and others jejunopseudocystostomy (97, 98). There are also advocates of individualised approach when operation is chosen according to the particular anatomy and condition of the patient (84). For example gastropseudocystostomy is recommended when the anastomosis can be performed through an area of fusion between the pseudocyst and the posterior wall of the stomach. When the pseudocyst is not fused to the posterior 172 Å. Andrén-Sandberg, C. Ansorge, K. Eiriksson, T. Glomsaker, A. Maleckas wall of the stomach a Roux-en-Y jejunopseudocystostomy is more likely to be the procedure of choice, because the consequences of the dehiscence of a long Roux-en-Y jejunopseudocystostomy are less catastrophic than a breakdown of an unfused gastropseudocystostomy or duodenopseudocystostomy (49). Whether postoperative hemorrhage can be reducing with oversewing a gastropseudocystostomy is a matter of debate. Some authors recommend oversewing it in the manner of an anastomosis with running suture (95, 98, 99), whereas others place multiple mattress sutures of permanent material circumferentially around the anastomosis in the area of fusion (49). There is also reported case of the use of disposable stapler for creation of gastropseudocystostomy (100). Hutson and colleagues (101) compared postoperative complications in patients with and without running sutures applied to the gastropseudocystic stomas. Two (33 %) of 6 patients in the suture group experienced postoperative bleeding as compared to none in the same size non-suture group. Authors suggested that oversewing the margins might interfere with gastric mucosal prolapse, which should serve as an effective mucosal valve preventing reflux of gastric contents into the cyst. When gastropseudocystic reflux occurs, the corrosive effects of gastric acid on the inflamed surface of the cyst wall might provoke hemorrhage. Contrary to the report of Hutson and colleagues (101) only 3 percent of the patients experienced bleeding from the sutured anastomosis between the stomach and the pseudocyst in the other published series (86, 95, 99). The incidence of major morbidity and of death seems to be similar between internal drainage procedures (49). In one series (102) two of 39 patients who underwent gastropseudocystostomy and two of 59 patients who underwent jejunopseudocystostomy died (operative mortality 5 % and 3 %, respectively). These statistics compare favourably to the 7 percent, 4 percent and 4 percent mortality rates after gastropseudocystostomy, jejunopseudocystostomy and duodenopseudocystostomy, respectively, found in the collective review of the literature. Morbidity rate was then 24 percent, 18 percent and 23 percent, respectively. RECURRENCE OF PSEUDOCYSTS Newell and colleagues (102) found no difference in pseudocyst recurrence with gastropseudocystostomy compared to jejunopseudocystostomy. Pseudocyst recurrence was 10 percent with gastropseudocystostomy and 7 percent with jejunopseudocystostomy. These rates compare favourably with the results of the other studies. In a review of 1020 patients, the cyst recurrence rate was 3 percent after gastropseudocystostomy and 5 percent after jejunopseudocystostomy (103). Mitty and colleagues (104) reported from the literature a recurrence rate of 6 percent in 365 cases after jejunopseudocystostomy, 3 percent in 415 cases after gastropseudocystostomy and 8 percent in 75 cases after duodenopseudocystostomy. Recurrence rates may indicate the true reappearance of pseudocysts treated with an enteropseudo- cystic anastomosis. However, development of newly formed pseudocysts due to a progression of pancreatic disease is also possible. As an aspect of the underlying chronic pancreatitis a high rate of attacks of acute pancreatitis after cyst drainage (33 %) can be observed (20, 50, 105, 106). Therefore, some of the reported “recurrences” may represent the progression of coexisting pseudocysts which were unappreciated at the time of the original drainage procedure (107). In the others loculated pseudocysts may recur due to failure to drain the most dependent part of the cyst, or failure to provide an adequate pseudocyst-enteric anastomosis. Thus, at the second operation it is often impossible to know if the pseudocyst is new, recurrent, persistent, or overlooked at the first operation (49). LAPAROSCOPIC TREATMENT Laparoscopic surgery has been recommended as a safe, reliable, and minimally invasive treatment for managing pancreatic pseudocyst (108) as advances in laparoscopic surgical technique and instrumentation have furthered our ability to perform more complex laparoscopic procedures (109). The minimally invasive approach to gastropseudocystostomy allows for wide drainage of the pancreatic pseudocysts and might avoid the greater morbidity and longer recovery from an open surgical procedure (110). Reports to date have consisted of case series, often with limited follow-up (109). A computerized search using the search words “pancreatic” and “pseudocysts” in 2003 showed that laparoscopic gastropseudocystostomy and jejunopseudocystostomy achieve adequate internal drainage, facilitate concomitant debridement of necrotic tissue within acute pseudocysts, and achieve good results with minimal morbidity (111). PSEUDOCYST RESECTION; RESECTION OF BODY AND TAIL OF PANCREAS Pancreatic resection – including the pseudocyst – is an alternative to internal drainage for chronic pseudocysts of moderate proportions, especially those that have largely replaced a portion of the pancreas. However, in most cases pseudocysts are surrounded by an intense inflammatory reaction, which produces dense adherence of adjacent organs to the cyst and obscures normal anatomic relationships (94). Therefore, pseudocysts localised to the neck and body of the gland are often densely adherent to the portal and superior mesenteric vessels posteriorly, and resection represents a difficult undertaking with cumulative results which are less acceptable than those occurring after internal drainage of gastropseudocystostomy or jejunopseudocystostomy (103). Indications for pancreatic resections include pseudoaneurysms associated with a pseudocyst, patients having multiple pseudocysts, or pseudocysts located in the uncinate process or head of the pancreas in which internal decompression is not technically fea- Treatment of pancreatic pseudocysts sible. Common duct or duodenal obstruction frequently cannot be relieved except by a pancreaticoduodenectomy due to the presence of one or smaller pseudocysts, which do not lend themselves to internal drainage. There are also advocates that also a small pseudocyst or pseudocysts in the head of the pancreas may initiate and perpetuate pancreatic inflammation and as Sankaran (6) and Nardi (112) have noted can produce very troublesome persistent symptoms. Sometimes these small cysts are not appreciated on ERCP and are impossible to identify by palpation at operation and are only recognised after pancreaticoduodenectomy is well under way (49). LEFT-SIDED RESECTIONS Left-sided resection, or distal pancreatectomy, are terms applied to resection of the portion of the pancreas extending to the left of the midline and not including the duodenum and distal bile duct. Despite the length of time distal pancreatectomy has been in existence the rate of morbidity is still quite significant with one-quarter to one-third of patients experiencing a postoperative complication (113, 114). However, early postoperative results of all kinds of pancreatic resections have improved dramatically over the two last decades, with decreased mortality and morbidity. This is not only due to advances in pancreatic surgery but also to better anesthesiology and perioperative care. Data concerning postoperative morbidity after pancreatic left resection show a wide range, with rates varying between 10 and 40 percent (115–120). In a French retrospective study, the morbidity among all the resected patients was 32 percent (121). Distal pancreatectomy should be performed with almost nil mortality (122– 124). Distal pancreatectomy can nowadays also be performed laparoscopically (125–127). RECOMMENDATIONS There are no randomized studies for the management protocols for pancreatic pseudocysts, and maybe it is seldom appropriate to randomize in this disease as it is difficult to find suitable patients where experience tell that any of types of management have the same possibility of a good outcome. Therefore, today we have to rely on best clinical practice, but still certain advice may be given: – differentiate acute from chronic pseudocysts for management – do not miss cystic neoplasias – always consider conservative treatment (do not treat pseudocysts just because they are there) – if intervention is needed, first consider a procedure that is well known; the results of percutaneous or endoscopic drainage are probably more dependent on the experience of the interventionist than the choice of procedure – if surgery is needed, wait until an intern anastomosis can hold sutures (if possible 6 weeks) 173 REFERENCES 001. Bradley EL: A clinically based classification system for acute pancreatitis. Arch Surg 1993;128:586–590 002. D’Egidio A, Schein M: Pancreatic pseudocysts: a proposed classification and its management implications. Br J Surg 1991;78:981–984 003. Sarles H, Muratore R, Sarles JC: Etude anatomique des pancreatites chroniques de l’adulte. Sem Hop 1961;25:1507–1522 (in French). 004. Sarles H, Martin M, Camatte R, Sarles JC: Le demembrement des pancreatities: Les pseudokystes des pancreatiles aigues et des pancreatites chroniques. Press Med 1963;5:237–240 (in French). 005. Bourliere M, Sarles H: Pancreatic cysts and pseudocysts associated with acute and chronic pancreatitis. Dig Dis Sci 1989;34:343–348 006. Sankaran S, Walt AJ: The natural and unnatural history of pancreatic pseudocysts. Br J Surg 1975;62:37–44 007. Hanna WA: Rupture of pancreatic cysts. Br J Surg 1960; 47:495–498 008. Aranha GV, Prinz RA, Esguerra AC, Greenlee HB: The nature and course of cystic pancreatic lesions diagnosed by ultrasound. Arch Surg 1983;118:486–488 009. Maringhini A, Uomo G, Patti R, Rabitti P, Termini A, Cavallera A, Dardanoni G, Manes G, Ciambra M, Laccetti M, Biffarella P, Pagliaro L: Pseudocysts in acute nonalcoholic pancreatitis: incidence and natural history. Dig Dis Sci 1999; 44:1669–1673 010. Warshaw AL, Rattner DW: Timing of surgical drainage for pancreatic pseudocyst. Clinical and chemical criteria. Ann Surg 1985;202:720–724 011. Forsmark CE, Grendell J: Complications of pancreatitis. Semin Gastrointest Dis 1991;2:165–176 012. Nguyen BL, Thompson JS, Edney JA, Bragg LE, Rikkers LF: Influence of the etiology of pancreatitis on the natural history of pancreatic pseudocysts. AmJ Surg 1991;162:527–531 013. Gouyon B, Levy P, Ruszniewski P, Zins M, Hammel P, Vilgrain V, Sauvanet A, Belghiti J, Bernades P: Predictive factors in the outcome of pseudocysts complicating alcoholic chronic pancreatitis. Gut 1997;41:821–825 014. Neoptolemos JP, London NJ, Carr–Locke DL: Assessment of main pancreatic duct integrity by endoscopic retrograde pancreatography in patients with acute pancreatitis. Br J Surg 1993;80:94–99 015. Sankaran S, Walt AJ: The natural and unnatural history of pancreatic pseudocysts. Br J Surg 1975;62:37–44 016. Agha FP: Spontaneous resolution of acute pancreatic pseudocysts. Surg Gynecol Obstet 1984;158:22–26 017. McConnell DB, Gregory JR, Sasaki TM, Vetto RM: Pancreatic pseudocyst. Am J Surg 1982;143:599–601 018. Pollack EW, Michas CA, Wolfman EF: Pancreatic pseudocyst: management in fifty–four patients. Am J Surg 1978;135: 199–201 019. Czaja AJ, Fisher M, Marin GA: Spontaneous resolution of pancreatic masses (pseudocysts?) – development and disappearance after acute alcoholic pancreatitis. Arch Intern Med 1975;135:558–562 020. Bradley E, Clements J, Gonzales AC: The natural history of pancreatic pseudocysts: a unified concept of management. Am J Surg 1979;137:135–141 021. Vitas GJ, Sarr MG: Selected management of pancreatic pseudocysts: operative versus expectant management. Surgery 1992;111:123–130 022. O’Malley VP, Cannon JP, Postier RG: Pancreatic pseudocysts: cause, therapy, and results. Am J Surg 1985;150:680– 682 023. Yeo CJ, Bastidas JA, Lynch-Nyhan A, Fishman EK, Zinner MJ, Cameron JL: The natural history of pancreatic pseudocysts documented by computed tomography. Surg Gynecol Obstet 1990;170:411–417 024. Vosoghi M, Sial S, Garrett B, Feng J, Lee T, Stabile BE, Eysselein VE: EUS-guided pancreatic pseudocyst drainage: review and experience at Harbor-UCLA Medical Center. Med Gen Med 2002;4:2 025. Adams DB, Anderson MC: Percutaneous catheter drainage compared with internal drainage in the management of pancreatic pseudocyst. Ann Surg 1992;6:571–578 174 Å. Andrén-Sandberg, C. Ansorge, K. Eiriksson, T. Glomsaker, A. Maleckas 026. Heider R, Meyer A, Galanko J, Behrns KE: Percutaneous drainage of pancreatic pseudocysts as associated with a higher failure rate than surgical treatment in unselected patients. Ann Surg 1999;229:781–789 027. Criado E, DeStefano A, Weiner T, Jaques P: Long term results of percutaneous catheter drainage of pancreatic pseudocysts. Surg Gynecol Obstet 1992;175:293–298 028. vanSonnenberg E, Wittich GR, Casola G, Brannigan TC, Karnel F, Stabile BE, Varney RR, Christensen RR: Percutaneous drainage of infected and noninfected pancreatic pseudocysts: experience in 101 cases. Radiology 1989;170:757–761 029. Boerma D, Obertop H, Gouma DJ: Pancreatic pseudocysts in chronic pancreatitis. Surgical or interventional drainage? Ann Ital Chir 2000;71:43–50 030. Gerzof SG, Johnson WC, Robbins AH, Spechler SJ, Nabseth DC: Percutaneous drainage of infected pancreatic pseudocysts. Arch Surg 1984;119:888–893 031. vanSonnenberg E, Wittich GR, Casola G, Stauffer AE, Polansky AD, Coons HG, Cabera OA, Gerver PS: Complicated pancreatic inflammatory disease: diagnostic and therapeutic role of interventional radiology. Radiology 1985;155:335– 340 032. Freeny PC, Lewis GP, Traverso LW, Ryan JA: Infected pancreatic fluid collections: percutaneous catheter drainage. Radiology 1988;167:435–441 033. Freeny PC: Percutaneous management of pancreatic fluid collections. Baillieres Clin Gastroenterol 1992;6:259–272 034. D’Egidio A, Schein M: Percutaneous drainage of pancreatic pseudocysts: a prospective study. World J Surg 1992;16:141– 146 035. Gumaste VV, Dave PB: Pancreatic pseudocyst drainage – the needle or the scalpel? J Clin Gastroenterol 1991;13:500–505 (Editorial) 036. Pitchumoni CS, Agarwal N: Pancreatic pseudocysts. When and how should drainage be performed? Gastroenterol Clin North Am 1999;28:615–639 037. Nealon WH, Walser E: Main pancreatic ductal anatomy can direct choice of modality for treating pancreatic pseudocysts (surgery versus percutaneous drainage). Ann Surg 2002;235: 751–758 038. Frey CF, Bradley EL: Progress in acute pancreatitis. Surg Gynecol Obstet 1988;167:282–286 039. Bradley EL, Murphy F, Ferguson C: Prediction of pancreatic necrosis by dynamic pancreatography. Ann Surg 1989;210: 495–503 040. Nealon WH, Townsend CM, Thompson JC: Preoperative endoscopic retrograde cholangiopancreatography (ERCP) in patients with pancreatic pseudocyst associated with resolving acute and chronic pancreatitis. Ann Surg 1989;209:532– 540 041. Mueller PR, Ferrucci JT, Simeone JF, Butch RJ, Wittenberg J, White M, Brown AS: Lesser sac abscesses and fluid collections: drainage by transhepatic approach. Radiology 1985; 155:615–618 042. Bradley EL, Gonzalez AC, Clements JL: Acute pancreatic pseudocysts: incidence and implications. Ann Surg 1976;184: 734–737 043. Martin EW, Catalano P, Cooperman M, Hecht C, Carey LC: Surgical decision-making in the treatment of pancreatic pseudocysts. Internal versus external drainage. Am J Surg 1979;138:821–824 044. Hancke S, Pedersen JF: Percutaneous puncture of pancreatic cysts guided by ultrasound. Surg Gynecol Obstet 1976;142: 551–552 045. Andersson R, Janzon M, Sundberg I, Bengmark S: Management of pancreatic pseudocysts. Br J Surg 1989;76:550–552 046. Aurell Y, Forsberg L, Hederstrom E, Andersson R: Percutaneous puncture and drainage of pancreatic pseudocysts. A retrospective study. Acta Radiol 1990;31:177–180 047. Henriksen FW, Hancke S: Percutaneous cystogastrostomy for chronic pancreatic pseudocyst. Br J Surg 1994;81:1525– 1528 048. Bodker A, Kjaergaard J, Schmidt A, Tilma A: Pancreatic pseudocysts. A follow-up study. Ann Surg 1981;194:80–84 049. Frey CF: Pancreatic pseudocyst – operative strategy. Ann Surg 1978;188:652–662 050. Kohler H, Schafmayer A, Ludtke FE, Lepsien G, Peiper JH: Surgical treatment of pancreatic pseudocysts. Br J Surg 1987; 74:813–815 051. Ahearne PM, Baillie J, Cotton PB, Baker ME, Meyers WC, Pappas TN: An endoscopic cholangiopancreatography (ERCP)-based algorithm for the management of pancreatic pseudocysts. Am J Surg 1992;163:111–115 052. Grosso M, Gandini G, Cassinis MC, Regge D, Righi D, Rossi P: Percutaneous treatment (including pseudocystogastrostomy) of 74 pancreatic pseudocysts. Radiology 1989;173:493– 497 053. Criado E, DeStefano A, Weiner T, Jaques P: Long term results of percutaneous catheter drainage of pancreatic pseudocysts. Surg Gynecol Obstet 1992;175:293–298 054. Himal HS, Cusimano RJ: Pancreatic pseudocysts: the role of percutaneous catheter drainage. Can J Surg 1992;35:403–406 055. Ng B, Murray B, Hingston G, Windsor JA: An audit of pancreatic pseudocyst management and the role of endoscopic pancreatography. Aust N Z J Surg 1998;68:847–851 056. Heider R, Meyer A, Galanko J, Behrns KE: Percutaneous drainage of pancreatic pseudocysts as associated with a higher failure rate than surgical treatment in unselected patients. Ann Surg 1999;229:781–789 057. Vidyarthi G, Steinberg SE: Endoscopic management of pancreatic pseudocysts. Surg Clin North Am 2001;81:405–410 058. Schutz SM, Leung JW: Pancreatic endotherapy for pseudocysts and fluid collections. Gastrointest Endosc 2002;56:150– 152 059. Vitale GC, Zavaleta CM: Endoscopic retrograde cholangiopancreatography for surgeons. Semin Laparosc Surg 2003; 10:19–27 060. Binmoeller KF, Seifert H, Walther A, Soehendra N: Transpapillary and transmural drainage of pancreatic pseudocysts. Gastrointest Endosc 1995;42:219–224 061. Smits ME, Rauws EAJ, Tytgat GNJ, Huibregtse K: The efficacy of endoscopic treatment of pancreatic pseudocysts. Gastrointest Endosc 1995;42:202–207 062. Cremer M, Deviere J, Engelholm L: Endoscopic management of cysts and pseudocysts in chronic pancreatitis: long term follow-up after 7 years of experience. Gastrointest Endosc 1989;35:1–9 063. Sahel J: Endoscopic drainage of pancreatic cysts. Endoscopy 1991;23:181–184 064. Huibregtse K, Schneider B, Vrij AA, Tytgat GNJ: Endoscopic pancreatic drainage in chronic pancreatitis. Gastrointest Endosc 1988;34:9–15 065. Grimm H, Meyer WH, Nahm Vch, Soehendra N: New modalities for treating chronic pancreatitis. Endoscopy 1989;21: 70–74 066. Kozarek RA, Ball TJ, Patterson DJ, Freeny PC, Ryan JA, Traverso LW: Endoscopic transpapillary therapy for disrupted pancreatic duct and peripancreatic fluid collections. Gastroenterology 1991;100:1362–1370 067. Barthet M, Sahel J, Bodiou-Bertel C, Bernard JP: Endoscopic transpapillary drainage of pancreatic pseudocysts. Gastrointest Endosc 1995;42:208–213 068. Catalano MF, Geenen JE, Schmalz MJ, Johnson GK, Dean RS, Hogan WJ: Treatment of pancreatic pseudocysts with ductal communication by transpapillary pancreatic duct endoprosthesis. Gastrointest Endosc 1995;42:214–218 069. Chak A: Endosonographic-guided therapy of pancreatic pseudocysts. Gastrointest Endosc 2000;52 Suppl: S23–27 070. Marshall GT, Howell DA, Hansen BL, Amberson SM, Abourjaily GS, Bredenberg CE: Multidisciplinary approach to pseudoaneurysms complicating pseudocysts. Impact of pretreatment diagnosis. Arch Surg 1996;131:278–283 071. Kozarek RA, Ball TJ, Patterson DJ, Freeny PC, Ryan JA, Traverso LW: Endoscopic transpapillary therapy for disrupted pancreatic duct and peripancreatic fluid collections. Gastroenterology 1991;100:1362–1370 072. Barthet M, Sahel J, Bodiou-Bertei C, Bernard JP: Endoscopic transpapillary drainage of pancreatic pseudocysts. Gastrointest Endosc 1995;42:208–213 073. Catalano MF, Geenen JE, Schmalz MJ, Johnson GK, Dean RS, Hogan WJ: Treatment of pancreatic pseudocysts with ductal communication by transpapillary pancreatic duct endoprosthesis. Gastrointest Endosc 1995;42:214–218 074. Baron TH, Harewood GC, Morgan DE, Yates MR: Outcome differences after endoscopic drainage of pancreatic necrosis, acute pancreatic pseudocysts, and chronic pancreatic pseudocysts. Gastrointest Endosc 2002;56:7–17 075. Sharma SS, Bhargawa N, Govil A: Endoscopic management Treatment of pancreatic pseudocysts 076. 077. 078. 079. 080. 081. 082. 083. 084. 085. 086. 087. 088. 089. 090. 091. 092. 093. 094. 095. 096. 097. 098. 099. 100. 101. 102. of pancreatic pseudocyst: a long-term follow-up. Endoscopy 2002;34:203–207 Kohler H, Schafmayer A, Ludtke FE, Lepsien G, Peiper JH: Surgical treatment of pancreatic pseudocysts. Br J Surg 1987; 74:813–815 Moran B, Rew DA, Johnson CD: Pancreatic pseudocysts should be treated by surgical drainage. Ann R Coll Surg Engl 1994;76:54–58 Williams KJ, Fabian TC: Pancreatic pseudocysts: recommendations for operative and nonoperative management. Am Surg 1992;58:199–205 Cooperman AM: Surgical treatment of pancreatic pseudocysts. Surg Clin North Am 2001;81:411–419 Grace PA, Williamson RC: Modern management of pancreatic pseudocysts. Br J Surg 1993;80:573–581 Laxson LC, Fromkes JJ, Cooperman M: Endoscopic retrograde cholangiopancreatography in the management of pancreatic pseudocysts. Am J Surg 1985;150:683–686 Sugawa C, Wait AJ: Endoscopic retrograde pancreatography in the surgery of pancreatic pseudocysts. Surgery 1979;86: 639–647 O’Connor M, Kolars J, Ansel H, Silvis S, Vennes J: Preoperative endoscopic retrograde cholangiopancreatography in the surgical management of pancreatic pseudocysts. Am J Surg 1986;151:18–24 Aranha GV, Prinz RA, Freeark RJ, Kruss DM, Greenlee HB: Evaluation of therapeutic options for pancreatic pseudocysts. Arch Surg 1982;117:717–721 Bumpers HL, Bradley EL: Treatment of pancreatic pseudocysts. In: Howard J, Idezuki Y, Ihse I, Prinz R, eds. Surgical diseases of the Pancreas. Baltimore: Williams and Wilkins, 1998:423–432 Shatney CH, Lillehei RC: Surgical treatment of pancreatic pseudocysts. Analysis of 119 cases. Ann Surg 1979;189:386– 394 Mullins RJ, Malangoni MA, Bergamini TM, Casey JM, Richardson JD: Controversies in the management of pancreatic pseudocysts. Am J Surg 1988;155:165–172 Warren WD, Marsh WH, Muller WH: Experimental production of pseudocysts of the pancreas with preliminary observations on internal drainage. Surg Gynecol Obstet 1957; 105:385–392 Grace RR, Jordan PH: Unresolved problems of pancreatic pseudocysts. Ann Surg 1976;184:16–21 Rattner DW, Warshaw AL: Pancreatic cysts, pseudocysts and fistulae. In: Schwartz SI, Ellis H, Eds. Maingot’s Abdominal Operations. Norwalk, Connecticut: Appleton-CenturyCrofts. 1990:1567–1582 Elechi EN, Callender CO, Leffall LD, Kurtz LH: The treatment of pancreatic pseudocysts by external drainage. Surg Gynecol Obstet 1979;148:707–710 Schattenkerk ME, De Vries JE, Bruining HA, Eggink WF, Obertop H: Surgical treatment of pancreatic pseudocysts. Br J Surg 1982;69:593–594 Bradley EL: Don’t fix nothin that ain’t broke. Am J Surg 1985;149:197 (Editorial) Anderson MC: Management of pancreatic pseudocysts. Am J Surg 1972;123:209–221 van Heerden JA, ReMine WH: Pseudocysts of the pancreas. Review of 71 cases. Arch Surg 1975;110:500–505 Bodurtha AJ, Dajee H, You CK: Analysis of 29 cases of pancreatic pseudocyst treated surgically. Can J Surg 1980;23: 432–434 Sandy JT, Taylor RH, Christensen RM, Scudamore C, Leckie P: Pancreatic pseudocyst. Changing concepts in management. Am J Surg 1981;141:574–576 Folk FA, Freeark RJ: Reoperations for pancreatic pseudocyst. Arch Surg 1970;100:430–437 Schumer W, McDonald GO, Nichols RL, Miller B: Transgastric cystogastrostomy. Surg Gynecol Obstet 1973;137:48–50 Yunoki Y, Takeuchi H, Yasui Y, Tanakaya K, Konaga E, Hamazaki K: Use of disposable stapler in operative cystogastrostomy for pancreatic pseudocyst. Hepatogastroenterology 1999;46:3271–3273 Hutson DG, Zeppa R, Warren DW: Prevention of postoperative hemorrhage after pancreatic cystogastrostomy. Ann Surg 1973;177:689–693 Newell KA, Liu T, Aranha GV, Prinz RA: Are cystgastrostomy and cystjejunostomy equivalent operations for pancre- 175 atic pseudocysts? Surgery 1990;108:635–639 103. Becker WF, Pratt HS, Ganji H: Pseudocysts of the pancreas. Surg Gynecol Obstet 1968;127:744–47 104. Mitty WJ, Nealon TF, Grossi CE, Clemett AR, Bonanno CA: Diagnostic adjunct in management of pseudocysts of the pancreas. Am J Gastroenterol 1974;62:204–209 105. Rossi RL, Heiss FW, Braasch JW: Surgical management of chronic pancreatitis. Surg Clin North Am 1985;65:79–101 106. Warren KW, Badosa K: Individualization in treatment of pancreatic pseudocysts. Ann Surg 1973;39:559–563 107. Goulet RJ, Goodman J, Schaffer R, Dallemand S, Andersen DK: Multiple pancreatic pseudocyst disease. Ann Surg 1984; 199:6–13. 108. Shimizu S, Morisaki T, Noshiro H, Mizumoto K, Yamaguchi K, Chijiiwa K, Tanaka M: Laparoscopic cystogastrostomy for pancreatic pseudocyst: a case report. JSLS 2000;4:309–312 109. Hagopian EJ, Teixeira JA, Smith M, Steichen FM: Pancreatic pseudocyst treated by laparoscopic Roux-en-Y cystojejunostomy. Report of a case and review of the literature. Surg Endosc 2000;14:967 110. Siperstein A: Laparoendoscopic approach to pancreatic pseudocysts. Semin Laparosc Surg 2001;8:218–222 111. Bhattacharya D, Ammori BJ: Minimally invasive approaches to the management of pancreatic pseudocysts: review of the literature. Surg Laparosc Endosc Percutan Tech 2003;13: 141–148 112. Nardi GL, Lyon DC, Sheiner HJ, Bartlett MK: Solitary occult retention cysts of the pancreas. N Engl J Med 1969; 280:11–15 113. Brennan MF, Moccia RD, Klimstra D: Management of adenocarcinoma of the body and tail of the pancreas. Ann Surg 1996;223:506–512 114. Lillemoe KD, Kaushal S, Cameron JL, Sohn TA, Pitt HA, Yeo CJ: Distal pancreatectomy: indications and outcomes in 235 patients. Ann Surg 1999;229:693–700 115. Aldridge MC, Williamson RC: Distal pancreatectomy with and without splenectomy. Br J Surg 1991;78:976–979 116. Lygidakis NJ, van der Hyde MN, Houhoff HJ, Schipper ME, Huibregtse K, Tytgat GN, Lubber MJ, Reeders JW, Bosey MM, Oosting J: Resectional surgical procedures for carcinoma of the head of the pancreas. Surg Gynecol Obstet 1989; 168:157–165 117. Brennan MF, Moccia RD, Klimstra D: Management of adenocarcinoma of the body and tail of the pancreas. Ann Surg 1996;223:506–512 118. Johnson CD, Schwall G, Flechtenmacher J, Trede M: Resection for adenocarcinoma of the body and tail of the pancreas. Br J Surg 1993;80:1177–1179 119. Dalton RR, Sarr MG, van Heerden JA, Colby TV: Carcinoma of the body and tail of the pancreas: is curative resections justified? Surgery 1992;111:489–494 120. Nordback IH, Hruban RH, Boitnott JK, Pitt HA, Cameron JL: Carcinoma of the body and tail of the pancreas. Am J Surg 1992;164:26–31 121. Fabre JM, Houry S, Manderscheid JC, Huguier M, Baumel H: Surgery of left-sided pancreatic cancer. Br J Surg 1996; 83:1065–1070 122. Shankar S, Theis B, Russell RCG: Management of the stump of the pancreas after distal resection. Br J Surg 1990;77:541– 544 123. Lillemoe KD, Kaushal S, Cameron JL, Sohn TA, Pitt HA, Yeo CJ: Distal pancreatectomy: indications and outcomes in 235 patients. Ann Surg 1999;229:693–700 124. Tihanyi TE, Morvay K, Nehez L, Winternitz T, Rusz Z, Flautner LE: Laparoscopic distal resection of the pancreas with preservation of the spleen. Acta Chir Hung 1997;36:359–361 125. Fernández-Cruz LF, Sáenz A, Pantoja JP: Minimally invasive pancreatic surgery: what is feasible? Pancreas 2000;21: 442 (Abstract) 126. Tagaya N, Kasama K, Suzuki N, Taketsuka S, Horie K, Kubota K: Laparoscopic resection of the pancreas. Hepato Biliary Pancreat Surg 2002;9 suppl 1:259 (Abstract) 127. Okuda J, Inoue H, Kawai M, Iwamoto M, Dohi T, Hayashi M, Hara H, Toyoda M, Morita S, Tanigawa N: Experience of laparoscopic surgery for pancreatic benign tumor. Hepato Biliary Pancreat Surg 2002;9 suppl 1:272 (Abstract) Received: June 6th, 2005