Percutaneous endoscopic necrosectomy for walled-off necrosis in the retroperitoneal space of the elderly:A case report

BACKGROUND Walled-off necrosis(WON)is a late complication of acute pancreatitis possibly with a fatal outcome.Even for WON spreading to the retroperitoneal space,percutaneous endoscopic necrosectomy(PEN)can be an alternate approach to surgical necrosectomy,particularly for the older individuals or patients with poor condition because of WON.CASE SUMMARY An 88-year-old man was admitted to our hospital with a jaundice.Endoscopic retrograde cholangiopancreatography(ERCP)was performed to improve jaundice;however,post-ERCP pancreatitis developed.The inflammation of pancreatitis spread widely from the right retroperitoneal cavity to the pelvis,and WON was formed 4 wk later.A percutaneous drainage tube was placed into the WON under computed tomography guidance.However,the drainage did not ameliorate clinical symptoms including fever,which assured less invasive necrosectomy.A metallic stent for the upper gastrointestinal(GI)tract was placed from the percutaneous drainage route.An upper GI endoscope was inserted into the inside of the WON through the metallic stent,and the necrotic tissues were bluntly removed with a snare forceps.Ten times of these necrosectomies resulted in the near-complete removal of necrotic tissues.These procedures consequently abated his fever and remarkable improvement in blood tests.CONCLUSION PEN for WON occurring in the retroperitoneal space was safe and effective for very old individuals.

Endoscopic ultrasonography-guided endoscopic treatment of pancreatic pseudocysts and walled-off necrosis:New technical developments

In the last decades,the treatment of pancreatic pseudocysts and necrosis occurring in the clinical context of acute and chronic pancreatitis has shifted towards minimally invasive endoscopic interventions.Surgical procedures can be avoided in many cases by using endoscopically placed,Endoscopic ultrasonography-guided techniques and drainages.Endoscopic ultrasound enables the placement of transmural plastic and metal stents or nasocystic tubes for the drainage of peripancreatic fluid collections.The development of selfexpanding metal stents and exchange free delivering systems have simplified the drainage of pancreatic fluid collections.This review will discuss available therapeutic techniques and new developments.

Short-and long-term results of endoscopic ultrasoundguided transmural drainage for pancreatic pseudocysts and walled-off necrosis

AIM To evaluate the short-and long-term results of endoscopic ultrasound-guided transmural drainage(EUS-GTD) for pancreatic fluid collection(PFC) and identify the predictive factors of treatment outcome for walled-off necrosis(WON) managed by EUS-GTD alone.METHODS We investigated 103 consecutive patients with PFC who underwent EUS-GTD between September 1999 and August 2015. Patients were divided into four groups as follows: WON(n = 40), pancreatic pseudocyst(PPC; n = 11), chronic pseudocyst(n = 33), and others(n = 19). We evaluated the short-and long-term outcomes of the treatment. In cases of WON, multiple logistic regression analyses were performed to identify the predictor variables associated with the treatment success. In addition, PFC recurrence was examined in patients followed up for more than 6 mo and internal stent removal after successful EUS-GTD was confirmed.RESULTS In this study, the total technical success rate was 96.1%. The treatment success rate of WON, PPC, chronic pseudocyst, and others was 57.5%, 90.9%, 91.0%, and 89.5%, respectively. Contrast-enhanced computed tomography using the multivariate logistic regression analysis revealed that the treatment success rate of WON was significantly lower in patients with more than 50% pancreatic parenchymal necrosis(OR = 17.0; 95%CI: 1.9-150.7; P = 0.011) and in patients with more than 150 mm of PFC(OR = 27.9; 95%CI: 3.4-227.7; P = 0.002).The recurrence of PFC in the long term was 13.3%(median observation time, 38.8 mo). Mean amylase level in the cavity was significantly higher in the recurrence group than in the no recurrence group(P = 0.02).CONCLUSION The reduction of WON by EUS-GTD alone was associated with the proportion of necrotic tissue and extent of the cavity. The amylase level in the cavity may be a predictive factor for recurrence of PFC.

Walled-off pancreatic necrosis

Walled-off pancreatic necrosis (WOPN), formerly known as pancreatic abscess is a late complication of acute pancreatitis. It can be lethal, even though it is rare. This critical review provides an overview of the continually expanding knowledge about WOPN, by review of current data from references identified in Medline and PubMed, to September 2009, using key words, such as WOPN, infected pseudocyst, severe pancreatitis, pancreatic abscess, acute necrotizing pancreatitis (ANP), pancreas, inflammation and alcoholism. WOPN comprises a later and local complication of ANP, occurring more than 4 wk after the initial attack, usually following development of pseudocysts and other pancreatic fluid collections. The mortality rate associated with WOPN is generally less than that of infected pancreatic necrosis. Surgical intervention had been the mainstay of treatment for infected peripancreatic fluid collection and abscesses for decades. Increasingly, percutaneous catheter drainage and endoscopic retrograde cholangiopancreatography have been used, and encourag-ing results have recently been reported in the medical literature, rendering these techniques invaluable in the treatment of WOPN. Applying the recommended therapeutic strategy, which comprises early treatment with antibiotics combined with restricted surgical intervention, fewer patients with ANP undergo surgery and interventions are ideally performed later in the course of the disease, when necrosis has become well demarcated.

Modified single transluminal gateway transcystic multiple drainage technique for a huge infected walled-off pancreatic necrosis: A case report

We report a successful endoscopic ultrasonographyguided drainage of a huge infected multilocular walledoff necrosis(WON) that was treated by a modified single transluminal gateway transcystic multiple drainage(SGTMD) technique. After placing a widecaliber fully covered metal stent, follow-up computed tomography revealed an undrained subcavity of WON. A large fistula that was created by the wide-caliber metal stent enabled the insertion of a forward-viewing upper endoscope directly into the main cavity, and the narrow connection route within the main cavity to the subcavity was identified with a direct view, leading to the successful drainage of the subcavity. This modified SGTMD technique appears to be useful for seeking connection routes between subcavities of WON in some cases.

Endoscopic gastric fenestration of debriding pancreatic walled-off necrosis: A pilot study

BACKGROUND Endoscopic drainage of walled-off necrosis(WON) is still a challenge due to stentassociated problems. We explored endoscopic gastric fenestration(EGF) as an innovative alternative intervention.AIM To assess the feasibility, efficacy and safety of EGF for WON.METHODS Between March 2019 and March 2020, five patients with symptomatic WON in close contact with the stomach wall were treated by EGF. Endoscopic ultrasound(EUS) was used to select appropriate sites for gastric fenestration, which then proceeded layer by layer as in endoscopic submucosal dissection. Both the stomach muscularis propria and pseudocyst capsule were penetrated. Fenestrations were expanded up to 1.5-3 cm for drainage or subsequent necrosectomy.RESULTS EGF failed in Case 1 due to nonadherence of WON to the gastric wall. EGF was successfully implemented in the other four cases by further refinement of fenestration site selection according to computed tomography, endoscopy and EUS features. The average procedure time for EGF was 124 min(EUS assessment, 32.3 min;initial fenestration, 28.8 min;expanded fenestration, 33 min), and tended to decrease as experience gradually increased. The diameter of the fenestration site was 1.5-3 cm, beyond the caliber of a lumen-apposing metal stent(LAMS), to ensure effective drainage or subsequent necrosectomy. Fenestration sites showed surprising capacity for postoperative self-healing within 1-3 wk. No EGF-related complications were seen. WON disappeared within 3 wk after EGF. In Case 3, another separate WON, treated by endoscopic LAMS drainage, recurred within 4 d after LAMS removal due to stent-related hemorrhage, and resolved slowly over almost 3 mo. No recurrences were observed in the five patients.CONCLUSION EGF is an innovative and promising alternative intervention for WON adherent to the gastric wall. The challenge resides in the gauging of actual adherence and in selecting appropriate fenestration sites.

Walled-off pancreatic necrosis:Wishing our pancreatitis nomenclature was correct

The ultimate reason why pancreatologists have strived to establish definitions for inflammatory pathologies of the pancreas is to improve patient care.Although the Atlanta Classification has been used for around for 17 years,considerable misunderstanding of the key elements of the nomenclature still persists.While a recent article by Stamatakos et al aimed to deal with an entity not clearly def ined in the 1993 document,it is replete with factual and conceptual errors as well as contradictory statements.

Simultaneous endoscopic and video-assisted retroperitoneal debridement in walled-off pancreatic necrosis using a laparoscopic access platform:Two case reports

BACKGROUND Infected walled-off necrosis is a potentially life-threatening complication of necrotizing pancreatitis.While some patients can be treated by drainage alone,many patients also need evacuation of the infected debris.Central necroses in relation to the pancreatic bed are easily reached via an endoscopic transluminal approach,whereas necroses that involve the paracolic gutters and the pelvis are most efficiently treated via a percutaneous approach.Large and complex necroses may need a combination of the two methods.CASE SUMMARY Transluminal and percutaneous drainage followed by simultaneous endoscopic and modified video-assisted retroperitoneal debridement was carried out in two patients with very large(32-38 cm),infected walled-off necroses using a laparoscopic access platform.After 34 d and 86 d and a total of 9 and 14 procedures,respectively,complete regression of the walled-off necroses was achieved.The laparoscopic access platform improved both access to the cavities as well as the overview.Simultaneous transluminal and percutaneous necrosectomy are feasible with the laparoscopic access platform serving as a useful adjunctive.CONCLUSION This approach may be necessary to control infection and achieve regression in some patients with complex collections.

Robot-assisted trans-gastric drainage and debridement of walled-off pancreatic necrosis using the EndoWrist stapler for the da Vinci Xi:A case report

BACKGROUND Walled-off pancreatic necrosis (WOPN) is a late complication of acute pancreatitis. The management of a WOPN depends on its location and on patient's symptoms. Trans-gastric drainage and debridement of WOPN represents an important surgical treatment option for selected patients. The da Vinci surgical System has been developed to allow an easy, minimally invasive and fast surgery, also in challenging abdominal procedures. We present here a case of a WOPN treated with a robotic trans-gastric drainage using the da Vinci Xi. CASE SUMMARY A 63-year-old man with an episode of acute necrotizing pancreatitis was referred to our center. Six wk after the acute episode the patient developed a walled massive fluid collection, with an extensive pancreatic necrosis, causing obstruction of the gastrointestinal tract. The patient underwent a robotic transgastric drainage and debridement of the WOPN performed with the da Vinci Xi platform. Firstly, an anterior ideal gastrotomy was carried out, guided by intraoperative ultrasound (US)-scan using the TilePro? function. Then, through the gastrotomy, the best location for drainage on the posterior gastric wall was again US-guided identified. The anastomosis between the posterior gastric wall and the walled-off necrosis wall was carried out with the new EndoWrist stapler with vascular cartridge. Debridement and washing of the cavity through the anastomosis were performed. Finally, the anterior gastrotomy was closed and the cholecystectomy was performed. The postoperative course was uneventful and a post-operative computed tomography-scan showed the collapse of the fluid collection. CONCLUSION In selected cases of WOPN the da Vinci Surgical System can be safely used as a valid surgical treatment option.

Multiple hidden vessels in walled-off necrosis with high-risk bleeding: Report of two cases

BACKGROUND Walled-off necrosis(WON),as a local complication of acute necrotizing pancreatitis,is difficult to differentiate from pancreatic pseudocysts(PPC).Imaging modalities such as computed tomography show a lower accuracy than endoscopic ultrasound(EUS)in confirming the diagnosis.EUS-guided cystogastrostomy following direct endoscopic necrosectomy has achieved excellent results and has been regarded as a preferred alternative to traditional surgery.However,highrisk bleeding is one of the greatest concerns.CASE SUMMARY Two patients with symptomatic pancreatic fluid collections(PFCs)were admitted to our hospital for EUS-guided lumen-apposing metal stent therapy.The female patient suffered from intermittent abdominal pain and underwent two perioperative CT examinations.The male patient had recurrent pancreatitis and showed a growing PFC.The initial diagnosis was a PPC according to contrast-enhanced CT.However,the evidence of solid contents on EUS prompted revision of the diagnosis to WON.An endoscope was inserted into the cavity,and some necrotic debris and multiple hidden vascular structures were observed.Owing to conservative treatment by irrigation with sterile water instead of direct necrosectomy,we successfully avoided damaging hidden vessels and reduced the risk of intraoperative bleeding.CONCLUSION The application of EUS is helpful for the identification of PFCs.Careful intervention should be conducted for WON with multiple vessels to prevent bleeding.

Comparative outcomes of endoscopic ultrasound-guided lumen-apposing mental stents drainage for pancreatic pseudocysts and walled-off necrosis:Case series and meta-analysis

Background:Endoscopic ultrasound(EUS)-guided transmural drainage for pancreatic fluid collections(PFCs)has become the first-line treatment with quicker recovery and more minor injury compared with surgery and percutaneous drainage.The efficacy of stents implantation and drainage for different PFCs remains controversial,especially lumen-apposing metal stents(LAMS).This study aimed to compare the efficacy and safety of LAMS drainage for pancreatic pseudocysts(PPC)and walled-off necrosis(WON).Methods:A meta-analysis was performed for LAMS drainage for WON and PPC by systematically searching PubMed,Cochrane,and Embase databases from January 2010 to January 2020.From 2017 to 2019,12 patients who were treated with LAMS drainage for PFCs in our medical center were also reviewed and included in this study.Results:Combining 11 copies of documents with the data from our medical center,a total of 585 patients with PFCs were enrolled in this meta-analysis,including 343 patients with WON and 242 with PPC.The technical success rate in WON is not significantly different from that of PPC(P=0.08>0.05).The clinical success of LAMS placement was achieved in 99%vs 89%in PPC and WON,respectively(RR=0.92,95%CI:0.86-0.98,P=0.01<0.05).The further intervention of direct endoscopic necrosectomy was required by 60%of patients in WON group.There was no significant difference in the incidence of adverse events,including infection,bleeding,stent migration and stent occlusion,after LAMS placement between WON and PPC.Conclusions:Endoscopic ultrasound-guided LAMS for PFCs are feasible,effective with preferable technical and clinical success rates.The clinical effect of LAMS on PPC is slightly better than that of WON,but its adverse reactions still need to be verified in a large-sample prospective study.

Management of patients after recovering from acute severe biliary pancreatitis

Cholelithiasis is the most common cause of acute pancreatitis,accounting 35%-60% of cases. Around 15%-20% of patients suffer a severe attack with high morbidity and mortality rates. As far as treatment is concerned,the optimum method of late management of patients with severe acute biliary pancreatitis is still contentious and the main question is over the correct timing of every intervention. Patients after recovering from an acute episode of severe biliary pancreatitis can be offered alternative options in their management,including cholecystectomy,endoscopic retrograde cholangiopancreatography(ERCP) and sphincterotomy,or no definitive treatment. Delaying cholecystectomy until after resolution of the inflammatory process,usually not earlier than 6 wk after onset of acute pancreatitis,seems to be a safe policy. ERCP and sphincterotomy on index admission prevent recurrent episodes of pancreatitis until cholecystectomy is performed,but if used for definitive treatment,they can be a valuable tool for patients unfit for surgery. Some patients who survive severe biliary pancreatitis may develop pseudocysts or walled-off necrosis. Management of pseudocysts with minimally invasive techniques,if not therapeutic,can be used as a bridge to definitive operative treatment,which includes delayed cholecystectomy and concurrent pseudocyst drainage in some patients. A management algorithm has been developed for patients surviving severe biliary pancreatitis according to the currently published data in the literature.

Management of pancreatic fluid collections: A comprehensive review of the literature

Pancreatic fluid collections(PFCs) are a frequent complication of pancreatitis. It is important to classify PFCs to guide management. The revised Atlanta criteria classifies PFCs as acute or chronic, with chronic fluid collections subdivided into pseudocysts and walled-off pancreatic necrosis(WOPN). Establishing adequate nutritional support is an essential step in the management of PFCs. Early attempts at oral feeding can be trialed in patients with mild pancreatitis. Enteral feeding should be implemented in patients with moderate to severe pancreatitis. Jejunal feeding remains the preferred route of enteral nutrition. Symptomatic PFCs require drainage; options include surgical, percutaneous, or endoscopic approaches. With the advent of newer and more advanced endoscopic tools and expertise, and an associated reduction in health care costs, minimally invasive endoscopic drainage has become the preferable approach. An endoscopic ultrasonography-guided approach using a seldinger technique is the preferred endoscopic approach. Both plastic stents and metal stents are efficacious and safe; however, metal stents may offer an advantage, especially in infected pseudocysts and in WOPN. Direct endoscopic necrosectomy is often required in WOPN. Lumen apposing metal stents that allow for direct endoscopic necrosectomy and debridement through the stent lumen are preferred in these patients. Endoscopic retrograde cholangio pancreatography with pancreatic duct(PD) exploration should be performed concurrent to PFC drainage. PD disruption is associated with an increased severity of pancreatitis, an increased risk of recurrent attacks of pancreatitis and long-term complications, and a decreased rate of PFC resolution after drainage. Any pancreatic ductal disruption should be bridged with endoscopic stenting.

Pancreatic fluid collections: What is the ideal imaging technique?

Pancreatic fluid collections(PFCs) are seen in up to 50% of cases of acute pancreatitis. The Revised Atlanta classification categorized these collections on the basis of duration of disease and contents, whether liquid alone or a mixture of fluid and necrotic debris. Management of these different types of collections differs because of the variable quantity of debris; while patients with pseudocysts can be drained by straight-forward stent placement, walledoff necrosis requires multi-disciplinary approach. Differentiating these collections on the basis of clinical severity alone is not reliable, so imaging is primarily performed. Contrast-enhanced computed tomography is the commonly used modality for the diagnosis and assessment of proportion of solid contents in PFCs; however with certain limitations such as use of iodinated contrast material especially in renal failure patients and radiation exposure. Magnetic resonance imaging(MRI) performs better than computed tomography(CT) in characterization of pancreatic/peripancreatic fluid collections especially for quantification of solid debris and fat necrosis(seen as fat density globules), and is an alternative in those situations where CT is contraindicated. Also magnetic resonance cholangiopancreatography is highly sensitive for detecting pancreatic duct disruption and choledocholithiasis. Endoscopic ultrasound is an evolving technique with higher reproducibility for fluid-to-debris component estimation with the added advantage of being a single stage procedure for both diagnosis(solid debris delineation) and management(drainage of collection) in the same sitting. Recently role of diffusion weighted MRI and positron emission tomography/CT with ^(18)F-FDG labeled autologous leukocytes is also emerging for detection of infection noninvasively. Comparative studies between these imaging modalities are still limited. However we look forward to a time when this gap in literature will be fulfilled.

Management of acute pancreatitis in Japan: analysis of nationwide epidemiological survey

Acute pancreatitis(AP) is an acute inflammatory disease of the exocrine pancreas. In Japan, nationwide epidemiological surveys have been conducted every 4 to 5 years by the Research Committee of Intractable Pancreatic Diseases, under the support of the Ministry of Health, Labour, and Welfare of Japan. We reviewed the results of the nationwide surveys focusing on the severity assessment and changes in the therapeutic strategy for walled-off necrosis. The severity assessment system currently used in Japan consists of 9 prognostic factors and the imaging grade on contrastenhanced computed tomography. By univariate analysis, all of the 9 prognostic factors were associated with AP-related death. A multivariate analysis identified 4 out of the 9 prognostic factors(base excess or shock, renal failure, systemic inflammatory response syndrome criteria, and age) that were associated with AP-related death. Receiver-operating characteristics curve analysis showed that the area under the curve was 0.82 for these 4 prognostic factors and 0.84 for the 9 prognostic factors, suggesting the comparable utility of these 4 factors in the severity assessment. We also examined the temporal changes in treatment strategy for walled-off necrosis in Japan according to the 2003, 2007, and 2011 surveys. Step-up approaches and lessinvasive endoscopic therapies were uncommon in 2003 and 2007, but became popular in 2011. Mortality has been decreasing in patients who require intervention for walled-off necrosis. In conclusion, the nationwide survey revealed the comparable utility of 4 prognostic factors in the severity assessment and the increased use of less-invasive, step-up approaches with improved clinical outcomes in the management of walled-off necrosis.

Is necrosectomy obsolete for infected necrotizing pancreatitis? Is a paradigm shift needed?

In 1886,Senn stated that removing necrotic pancreatic and peripancreatic tissue would benefit patients with severe acute pancreatitis.Since then,necrosectomy has been a mainstay of surgical procedures for infected necrotizing pancreatitis(NP).No published report has successfully questioned the role of necrosectomy.Recently,however,increasing evidence shows good outcomes when treating walled-off necrotizing pancreatitis without a necrosectomy.The literature concerning NP published primarily after 2000 was reviewed;it demonstrates the feasibility of a paradigm shift.The majority(75%)of minimally invasive necrosectomies show higher completion rates:between 80%and 100%.Transluminal endoscopic necrosectomy has shown remarkable results when combined with percutaneous drainage or a metallic stent.Related morbidities range from 40%to 92%.Single-digit mortality rates have been achieved with transluminal endoscopic necrosectomy,but not with video-assisted retroperitoneal necrosectomy series.Drainage procedures without necrosectomy have evolved from percutaneous drainage to transluminal endoscopic drainage with or without percutaneous endoscopic gastrostomy access for laparoscopic instruments.Most series have reached higher success rates of 79%-93%,and even 100%,using transcystic multiple drainage methods.It is becoming evident that transluminal endoscopic drainage treatment of walledoff NP without a necrosectomy is feasible.With further refinement of the drainage procedures,a paradigm shift from necrosectomy to drainage is inevitable.

Current status of treatments of pancreatic and peripancreatic collections of acute pancreatitis

Pancreatic and peripancreatic collections are the main local complications of acute pancreatitis with a high incidence.In the early phase,most acute pancreatic and peripancreatic collections can resolve spontaneously with supportive treatment.However,in some cases,they will develop into pancreatic pseudocyst(PPC)or walled-off necrosis(WON).When causing symptoms or coinfection,both PPC and WON may require invasive intervention.Compared to PPC,which can be effectively treated by endoscopic ultrasound-guided transmural drainage with plastic stents,the treatment of WON is more complicated and challenging,particularly in the presence of infected necrosis.In the past few decades,with the development of minimally invasive interventional technology especially the progression of endoscopic techniques,the standard treatments of those severe complications have undergone tremendous changes.Currently,based on the robust evidence from randomized controlled trials,the step-up minimally invasive approaches have become the standard treatments for WON.However,the pancreatic fistulae during the surgical step-up treatment and the stent-related complications during the endoscopic step-up treatment should not be neglected.In this review article,we will mainly discuss the indications of PPC and WON,the timing for intervention,and minimally invasive treatment,especially endoscopic treatment.We also introduced our preliminary experience in endoscopic gastric fenestration,which may be a promising innovative method for the treatment of WON.

Decreased serum platelet derived growth factor BB levels in acute and increased in chronic pancreatitis

AIM: To examine circulating growth factor concentrations in patients with acute pancreatitis (AP) and chronic pancreatitis (CP), and walled-off pancreatic necrosis (WOPN).

Invasive intervention timing for infected necrotizing pancreatitis: Late invasive intervention is not late for collection

With the advance of invasive interventions,the treatment model for infected necrotizing pancreatitis(INP)has shifted from open surgery to the step-up minimally invasive treatment.Late intervention,originating from the open surgery era,has been questioned in the minimally invasive period.With the emergence of new high-quality evidence about the timing for intervention,it seems to be increasingly apparent that,even in the age of minimal invasiveness,“late intervention”waiting for the necrotic collections to be encapsulated is still necessary.This opinion review mainly discusses the intervention timing for INP.

Management of the late effects of disconnected pancreatic duct syndrome: A case report

BACKGROUND There have been few reports about the late effects of disconnected pancreatic duct syndrome(DPDS). Although few reports have described the recurrence interval of pancreatitis, it might be rare for recurrence to occur more than 5 years later.Herein, we describe a case of recurrence in an 81-year-old man after the treatment of walled-off necrosis(WON) with pancreatic transection 7 years ago.CASE SUMMARY An 81-year-old man visited our hospital with chief complaints of fever and abdominal pain 7 years after the onset of WON due to severe necrotic pancreatitis. His medical history included an abdominal aortic aneurysm(AAA),hypertension, dyslipidemia, and chronic kidney disease. Computed tomography(CT) scan showed that the pancreatic fluid collection(PFC) had spread to the aorta with inflammation surrounding it, and CT findings suggested that bleeding occurred from the vasodilation due to splenic vein occlusion. First, we attempted to perform transpapillary drainage because of venous dilation around the residual stomach and the PFC. However, pancreatic duct drainage failed because of complete main pancreatic duct disruption. Second, we performed endoscopic ultrasound-guided drainage. After transmural drainage, the inflammation improved and stenting for the AAA was performed successfully. The inflammation was resolved, and he has been free from infection for more than 2 years after the procedure.CONCLUSION This case highlights the importance of continued follow-up of patients for recurrence after the treatment of WON with pancreatic transection.