Endoscopic snare papillectomy: a possible radical treatment for a subgroup of T1 ampullary adenocarcinomas

Transduodenal ampullectomy for early ampullary cancer: Clinical management, histopathological findings and long-term outcomes at a single center

BACKGROUND

Transduodenal ampullectomy has been attempted in ampullary tumors, including early ampullary cancer. However, the indication and extent of transduodenal ampullectomy with curative intent remain controversial. Herein, we address the perioperative and long-term outcomes of patients with early ampullary cancer who underwent transduodenal ampullectomy at a single center.

METHODS

We retrospectively enrolled 10 early ampullary cancer patients who underwent transduodenal ampullectomy and 11 early ampullary cancer patients who underwent subtotal stomach-preserving pancreatoduodenectomy at Saitama Cancer Center between October 2008 and May 2021. Among this cohort, we analyzed the perioperative outcomes and long-term outcomes.

RESULTS

In terms of the perioperative outcomes between the transduodenal ampullectomy and subtotal stomach-preserving pancreatoduodenectomy groups, the transduodenal ampullectomy group exhibited a shorter operating time (244 minutes vs 390 minutes, P = .003), less intraoperative blood loss (67.5 grams vs 774 grams, P = .006) and shorter length of postoperative hospital stay (15 days vs 33 days). With respect to the postoperative nutrition status, the transduodenal ampullectomy group exhibited less postoperative weight loss (0.67% vs 8.95%, P = .021), a better Controlling Nutritional Status score (1.0 vs 2.1, P = .011) and a better Prognostic Nutritional Index score (42.9 vs 40.9, P = .018). The 5-year survival in the adenoma with high-grade dysplasia and T1 ampullary cancer which invaded the mucosal layer groups was 100%, whereas the median survival time in the T1 ampullary cancer which invaded the sphincter of Oddi group was 20.7 months (P = .0028).

CONCLUSION

Transduodenal ampullectomy is assumed to be a feasible and effective surgical procedure for the treatment of selected patients with early ampullary cancer, including patients with adenoma with high-grade dysplasia or T1 ampullary cancer which invaded the mucosal layer ampullary cancer.

Long-term outcomes of endoscopic papillectomy for ampullary adenoma with high-grade dysplasia or adenocarcinoma: a propensity score-matched analysis

BACKGROUND

Evidence of endoscopic papillectomy (EP) for ampullar adenoma with high-grade dysplasia (HGD) or adenocarcinoma is insufficient. Here we investigated the long-term outcomes of the advanced ampullary tumors treated by EP with careful surveillance comparing to subsequent surgery after EP.

METHODS

Patients treated with EP for ampullary adenoma with HGD or adenocarcinoma from the multi-center retrospective Korean cohort of ampulla of Vater tumor were categorized into EP alone versus EP with subsequent surgery groups. The overall survival (OS) and recurrence-free survival (RFS) were analyzed for unmatched and matched cohorts using propensity score with nearest neighbor method.

RESULTS

During a median 43.3 months of follow-up, 5-year OS was not significantly different between the EP alone and EP surgery groups (91.9% vs. 82.3%, P = 0.443 for unmatched cohort; 89.2% vs. 82.3%, P = 0.861 for matched cohort, respectively). Furthermore, 5-year RFS was not significantly different between the two groups (82.1% vs. 86.7%, P = 0.520 for unmatched cohort; 66.1% vs. 86.7%, P = 0.052 for matched cohort, respectively). However, the patients with positive both (lateral and deep) margins showed significantly poorer survival outcomes than those with negative margins within the EP alone group (P = 0.007).

CONCLUSION

EP alone with careful surveillance showed comparable survival outcomes to those of EP with subsequent surgery for ampullar HGD or adenocarcinoma. Resection margin status could be a parameter to determine whether to perform subsequent radical surgery after EP.

Endoscopic Papillectomy

Most ampullary lesions (ALs) are sporadic, involve the major papilla, and are premalignant (adenomas). They are often diagnosed as an incidental finding during endoscopy or imaging procedures. Diagnosis and staging of ALs include endoscopic, histologic, and radiological evaluations. Currently, endoscopic papillectomy is the preferred treatment for ALs in most situations. In this article, we will describe the diagnostic work-up and focus on the endoscopic treatment, including indications, technique, outcomes, complications, and follow-up.

Clinical practice guidelines for endoscopic papillectomy

The Japan Gastroenterological Endoscopy Society has developed the "Clinical Practice Guidelines for Endoscopic Papillectomy (EP)" as a fundamental guideline using scientific approach. EP is a recently spreading therapeutic modality for ampullary tumors ranked as high risk endoscopic technique. Because of the paucity of high level of evidence, strength of recommendations had to be determined by a consensus among specialists. These guidelines, shed light on the following five issues: Indications, Preoperative/intraoperative preparations and techniques, Early adverse events, Therapeutic outcomes and remnants/recurrences, and Follow-up and late adverse events, to guide current clinical practice on EP.

Transduodenal ampullectomy for ampullary tumor

BACKGROUND

Transduodenal ampullectiomy (TDA) is a surgical local excision method that can be performed in patients with ampullary tumors, but it has not been widely used clinically. Recently, TDA is considered as a good alternative surgical technique in patients who are unable to perform the endoscopic ampullectomy (EA) or pancreaticoduodenectomy (PD) for various reasons. The purpose of this study is to evaluate the surgical outcomes of TDA and the clinicopathological significance of pathologic findings in TDA.

METHODS

We reviewed the medical records of 31 patients diagnosed as ampullary tumor and underwent TDA from March 2004 to December 2019 in a single center.

RESULTS

All 31 patients were planned to perform TDA, and 4 of them were converted to PPPD due to the marginal status results of frozen biopsy. Of the 31 patients, 19 were diagnosed with malignancy and 12 were diagnosed with benign. Of the 18 patients who were diagnosed as malignancy in final biopsy, only 9 patients (50%) were diagnosed with malignancy on the preoperative endoscopic biopsy. In 15 patients who underwent only TDA for malignancy, there was no recurrence during the follow-up period (mean: 51.1 months, range: 19-137).

CONCLUSIONS

In benign ampullary tumor, TDA is a choice of treatment for patients who are unsuitable for endoscopic ampullectomy. TDA may be considered as an alternative operation in highly selective patients with early ampullary cancer (Tis and T1). Further studies on consensus of TDA indication for ampullary tumor will be needed in the future.

Clinical practice guidelines for the management of biliary tract cancers 2019: The 3rd English edition

BACKGROUND

The Japanese Society of Hepato-Biliary-Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract cancers (cholangiocarcinoma, gallbladder cancer, and ampullary cancer) in 2007, then published the 2nd version in 2014.

METHODS

In this 3rd version, clinical questions (CQs) were proposed on six topics. The recommendation, grade for recommendation, and statement for each CQ were discussed and finalized by an evidence-based approach. Recommendations were graded as Grade 1 (strong) or Grade 2 (weak) according to the concepts of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system.

RESULTS

The 31 CQs covered the six topics: (a) prophylactic treatment, (b) diagnosis, (c) biliary drainage, (d) surgical treatment, (e) chemotherapy, and (f) radiation therapy. In the 31 CQs, 14 recommendations were rated strong and 14 recommendations weak. The remaining three CQs had no recommendation. Each CQ includes a statement of how the recommendations were graded.

CONCLUSIONS

This latest guideline provides recommendations for important clinical aspects based on evidence. Future collaboration with the cancer registry will be key for assessing the guidelines and establishing new evidence.

Endoscopic pancreaticobiliary drainage with overlength stents to prevent delayed perforation after endoscopic papillectomy: A pilot study

BACKGROUND

Endoscopic papillectomy (EP) is rapidly replacing traditional surgical resection and is a less invasive procedure for the treatment of duodenal papillary tumors in selected patients. With the expansion of indications, concerns regarding EP include not only technical difficulties, but also the risk of complications, especially delayed duodenal perforation. Delayed perforation after EP is a rare but fatal complication. Exposure of the artificial ulcer to bile and pancreatic juice is considered to be one of the causes of delayed perforation after EP. Draining bile and pancreatic juice away from the wound may help to prevent delayed perforation.

AIM

To evaluate the feasibility and safety of placing overlength biliary and pancreatic stents after EP.

METHODS

This is a single-center, retrospective study. Five patients with exposure or injury of the muscularis propria after EP were included. A 7-Fr overlength biliary stent and a 7-Fr overlength pancreatic stent, modified by an endoscopic nasobiliary drainage tube, were placed in the common bile duct and pancreatic duct, respectively, and the bile and pancreatic juice were drained to the proximal jejunum.

RESULTS

EP and overlength stents placement were technically feasible in all five patients (63 ± 12 years), with an average operative time of 63.0 ± 5.6 min. Of the five lesions (median size 20 mm, range 15-35 mm), four achieved en bloc excision and curative resection. The final histopathological diagnoses of the endoscopic specimen were one tubular adenoma with high-grade dysplasia (HGD), one tubulovillous adenoma with low-grade dysplasia, one hamartomatous polyp with HGD, one poorly differentiated adenocarcinoma and one atypical juvenile polyposis with tubulovillous adenoma, HGD and field cancerization invading the muscularis mucosae and submucosa. There were no stent-related complications, but one papillectomy-related complication (mild acute pancreatitis) occurred without any episodes of bleeding, perforation, cholangitis or late-onset duct stenosis.

CONCLUSION

For patients with exposure or injury of the muscularis propria after EP, the placement of overlength biliary and pancreatic stents is a feasible and useful technique to prevent delayed perforation.

Systematic Review with Meta-Analysis: Endoscopic and Surgical Resection for Ampullary Lesions

Ampullary lesions (ALs) can be treated by endoscopic (EA) or surgical ampullectomy (SA) or pancreaticoduodenectomy (PD). However, EA carries significant risk of incomplete resection while surgical interventions can lead to substantial morbidity. We performed a systematic review and meta-analysis for R0, adverse-events (AEs) and recurrence between EA, SA and PD. Electronic databases were searched from 1990 to 2018. Outcomes were calculated as pooled means using fixed and random-effects models and the Freeman-Tukey-Double-Arcsine-Proportion-model. We identified 59 independent studies. The pooled R0 rate was 76.6% (71.8–81.4%, I² = 91.38%) for EA, 96.4% (93.6–99.2%, I² = 37.8%) for SA and 98.9% (98.0–99.7%, I² = 0%) for PD. AEs were 24.7% (19.8–29.6%, I² = 86.4%), 28.3% (19.0–37.7%, I² = 76.8%) and 44.7% (37.9–51.4%, I² = 0%), respectively. Recurrences were registered in 13.0% (10.2–15.6%, I² = 91.3%), 9.4% (4.8–14%, I² = 57.3%) and 14.2% (9.5–18.9%, I² = 0%). Differences between proportions were significant in R0 for EA compared to SA (p = 0.007) and PD (p = 0.022). AEs were statistically different only between EA and PD (p = 0.049) and recurrence showed no significance for EA/SA or EA/PD. Our data indicate an increased rate of complete resection in surgical interventions accompanied with a higher risk of complications. However, studies showed various sources of bias, limited quality of data and a significant heterogeneity, particularly in EA studies.

A Comparison of Clinical Outcomes between Endoscopic Resection and Surgical Resection in Ampullary Tumors

Background and objectives: This study aimed to elucidate the clinical outcomes of endoscopic resection (ER) through comparison with surgical resection (SR) through a meta-analysis. Materials and Methods: This meta-analysis was performed using 32 studies. The complete resection and recurrence rates of treatment for ampullary tumors were investigated and compared between ER and SR. In addition, complications, including pancreatitis, cholangitis, cholecystitis, perforation, and papillary stenosis, and mortality of ER and SR, respectively, were estimated. Results: The rates of complete resection were 0.812 (95% confidence interval, CI, 0.758–0.856) and 0.929 (95% CI 0.739–0.984) in ER and SR, respectively. Recurrence rates were 0.145 (95% CI 0.107–0.193) and 0.126 (95% CI 0.057–0.257) in ER and SR, respectively. There were no significant differences in complete resection and recurrence rates between ER and SR in the meta-regression tests (p = 0.164 and p = 0.844, respectively). The estimated rates of pancreatitis, cholangitis/cholecystitis, perforation, and papillary stenosis were 12.8%, 4.4%, 5.2%, and 4.3% in ER and 9.9%, 5.6%, 2.3%, and 5.6% in SR, respectively. There was no significant difference in complications between ER and SR. The mortality rate of SR was slightly higher than that of ER (0.041, 95% CI 0.015–0.107 vs. 0.031, 95% CI 0.005–0.162). Our results show that ER had no significant differences in terms of complete resection and recurrence rates compared to SR, regardless of tumor behaviors. Conclusions: By comparing the complication and mortality rates between ER and SR, the safety of ER was proven.

Trans-duodenal ampullectomy for ampullary neoplasms: early and long-term outcomes in 36 consecutive patients

BACKGROUND

Trans-duodenal ampullectomy (TDA) is a surgical option for the treatment of selected ampullary neoplasms. The aim of this study was to evaluate our experience with TDA for the treatment of ampullary neoplasms, focusing on indications, technical aspects, and short- and long-term outcomes.

METHODS

All TDAs for ampullary neoplasms performed between January 2010 and December 2018 at our institution were retrospectively evaluated. Patients had ampullary neoplasms with low-grade dysplasia or in situ carcinoma (Tis) not suitable for an endoscopic approach, ampullary carcinoma unfit for pancreaticoduodenectomy (PD), or ampullary neuroendocrine G1-tumours.

RESULTS

Thirty-six patients were included in the study: 9 (25.0%) with neoplasms with low-grade dysplasia, 4 (11.1%) with G1 neuroendocrine tumours and 23 (63.9%) with Tis or invasive carcinoma. Mean operative time was 252.5 min. Overall and severe (Clavien-Dindo > IIIa) morbidity rate was 44.4% and 13.9%, respectively. No 90-day mortality was observed. At follow-up, no deaths were observed and local recurrence rate was 11.1% for patients with ampullary adenomas with low-grade dysplasia. Among four patients with neuroendocrine neoplasms, only one developed recurrence (pulmonary). Tis, T1 and T2 lesions were found in 16 (69.6%), 2 (8.7%) and 5 (21.7%) patients, respectively: recurrence occurred in 3 patients with Tis lesions (one malignant), no patients with T1 neoplasms and 2 patients with T2 lesions (3 patients had a survival of > 3 years).

CONCLUSIONS

TDA is a feasible and effective surgical procedure for the treatment of ampullary adenomas with low-grade dysplasia when endoscopic approach is contraindicated or has failed. For lesions with evidence of malignancy, TDA seems to be an oncological safe procedure for Tis ampullary cancer and a good palliative procedure for patients unfit for PD. Moreover, TDA may be appropriate for the treatment of G1 ampullary neuroendocrine neoplasms. A large multicentre study of TDA for early ampullary cancers is needed.

Endoscopic snare papillectomy for adenoma of the ampulla of vater: Long-term results in 135 consecutive patients

BACKGROUND

The premalignant nature of ampullary adenomas justifies their radical excision.

AIMS

Aim of this study is to evaluate the long-term results of endoscopic snare papillectomy in a consecutive series of patients with ampullary adenomas.

METHODS

Patients who underwent endoscopic snare papillectomy between October 1999 and October 2017 were identified from an electronic database. Endoscopic snare papillectomy was performed en bloc, when possible; a pancreatic stent or a nasopancreatic drainage were inserted. Endoscopic follow-up was scheduled after 3, 6 and 12 months for the first year, then yearly.

RESULTS

Endoscopic snare papillectomy was performed in 135 patients (70 M, mean age 60.5 years) by en bloc (83%) or piecemeal (17%) resection. Delayed bleeding occurred in 16 patients (11.8%), infected retroperitoneal collections in 6 patients (4.4%), pancreatitis in 4 patients (3%). One patient died (0.7%). Follow-up was available in 103/114 (90.3%) patients. In case of residual (24.3%) and recurrent (23.3%), adenomas endoscopic retreatment was successful in 42/49 cases (85.7%). After a mean follow-up of 40 months, 93.2% (96/103) of the patients were disease free CONCLUSION: Endoscopic snare papillectomy of ampullary adenomas is effective with favorable long-term outcomes. Compliance to the scheduled follow-up is important for the early detection and re-treatment of recurrences.

Methods and outcome of the endoscopic treatment of ampullary tumors

Ampullary tumors are rare neoplasms but increasingly encountered due to an increase in diagnostic procedures, mainly upper gastrointestinal endoscopy. Diagnosis, staging, and treatment of these tumors are described and recommendations given based on the most recent literature.

Four Neuroendocrine Tumor Types and Neuroendocrine Carcinoma of the Duodenum: Analysis of 203 Cases

BACKGROUND

Several types of neuroendocrine neoplasms (NENs) have been described in the duodenal tract, from low-grade tumors (NETs) to high-grade neuroendocrine carcinomas (NECs). A comprehensive analysis of histology, hormonal profile and prognostic parameters of a sufficiently large duodenal NEN series to cover all main kinds of neoplasms is however lacking.

METHODS

We collected a retrospective series of 203 duodenal wall and ampullary region NENs, from six specialized endocrine pathology centers. All were characterized histopathologically and histochemically, and 190 were followed for a median of 9 years.

RESULTS

Twenty-seven poorly differentiated NECs, mostly from the ampullary region, were identified and shown to lead to patient demise in a median of 10 months. Among 176 NETs, four subtypes were characterized, including 20 gastrinomas, 37 ampullary-type somatostatin-producing NETs (ASTs), 12 gangliocytic paragangliomas (GPs) and 106 nonfunctioning NETs (nfNETs). ASTs and GPs were mostly localized in the ampullary/periampullary region, while gastrinomas and nfNETs were mainly from the proximal duodenum. ASTs and gastrinomas showed high rates of local infiltration (especially lymphoinvasion and deep duodenal wall/pancreatic tissue invasion) and lymph node metastasis, while nfNETs had significantly lower and more size-dependent local invasive potential. Disease-specific survival differed significantly between NETs and NECs, though not among NET subtypes. NET cases with distant metastases (n = 23) were significantly associated with larger size, higher proliferative grade, lymphovascular invasion, deep invasion and local lymph node metastasis.

CONCLUSION

Our careful analysis of a large series of duodenal NENs identified five histologically and prognostically different histotypes of potential clinical relevance.

Transduodenal Ampullectomy for the Treatment of Early-Stage Ampulla of Vater Cancer

BACKGROUND

Transduodenal ampullectomy (TDA) is a less invasive procedure than pancreaticoduodenectomy (PD). However, the outcomes of TDA and PD have been compared rarely in early ampullary cancer.

METHODS

From September 1994 to June 2013, the patients who underwent curative surgery for Tis or T1 ampulla of Vater neoplasm were identified. The patients were divided into two groups according to the types of surgery; TDA group and PD group. The patient characteristics and survival outcomes were retrospectively investigated between the two groups.

RESULTS

Total 137 patients were included in this study. The 18 patients underwent TDA and 119 patients underwent PD for Tis or T1 ampullary cancer. There was no lymph node metastasis in the patients with Tis tumor although 10 of 104 patients had lymph node metastasis in T1 cancer. After a median follow-up of 50 months (range, 6-148), there were no recurrence after TDA for Tis tumor. However, the TDA was associated with higher local recurrence rate than PD in the patients with T1 ampullary cancer on Kaplan-Meier survival analysis (p = 0.007).

CONCLUSION

The TDA is feasible treatment for Tis ampulla of Vater neoplasm. However, TDA is unsuitable for the treatment of T1 ampulla of Vater cancer.

Can endoscopic papillectomy be curative for early ampullary adenocarcinoma of the ampulla of Vater?

BACKGROUND

The therapeutic role of endoscopic papillectomy (EP) for early ampullary cancer (AC) is still controversial. The aim of the present study was to evaluate the curative potential of EP for early AC and to identify predictors of lymph node metastases (LNMs).

METHODS

We retrospectively reviewed 173 patients who were prospectively included in a database and who underwent EP between 1999 and 2013. Adenocarcinoma was present in 28 resected specimens. An additional surgery was proposed in cases of duodenal submucosal infiltration, duct ingrowth, R1 resection or lymphovascular invasion. Clinicopathological information and outcomes were collected, and predictors of LNMs were evaluated.

RESULTS

Duodenal submucosal invasion was present in 16/28 cases and LNMs, in 9/28 cases. ACs of the biliopancreatic subtype were smaller (NS); 100 % had submucosal invasion, and 71 % had LNMs. Smaller tumour size, biliopancreatic subtype and submucosal invasion were significantly correlated with LNMs (p < 0.028, p < 0.028 and p < 0.014). Predictive factors of LNMs in the multivariate analysis were submucosal invasion and tumour size (OR 0.032, p < 0.023 and OR 0.711, p < 0.035). EP was curative in 100 % of cancers with R0 resection and no evidence of submucosal or lymphovascular invasion.

CONCLUSION

EP may be curative for patients with AC limited to the duodenal mucosa or the sphincter of Oddi without lymphovascular invasion. Due to the presence of more invasive stages at diagnosis, EP may not be curative for ACs of the biliopancreatic subtype. The significance of tumour size is limited by other confounders, such as the histological subtype.

Characteristic endoscopic ultrasound findings of ampullary lesions that predict the need for surgical excision or endoscopic ampullectomy

Background and Objectives:

The management of ampullary lesions has evolved to include endoscopic ampullectomy (EA) as a curative approach to cancers of the ampulla of Vater. With this change comes a need to risk-stratify patients at initial diagnosis.

Materials and Methods:

Patients with verified ampullary lesions (N = 50) were analyzed in a case-control design. We evaluated endoscopic ultrasound (EUS) data to define characteristics that yield a high sensitivity in selecting candidates for EA.

Results:

Using data from previously published studies yielded a sensitivity of 0.765 in appropriately identifying the 34 surgical cases. Expanding these characteristics increased the sensitivity of EUS to 0.971 in identifying surgical candidates. Additionally, of advanced disease cases, the expanded characteristics correctly identified these cases with a sensitivity of 1.0-improved over 0.708 using prior published data.

Conclusion:

EA should be strongly considered if ampullary lesions are found to fit the following characteristics after EUS evaluation: lesion size <2.5 cm, invasion ≤4 mm, pancreatic duct dilatation ≤3 mm, ≤T1 lesion, no lymph nodes present, and no ductal stent in place. Furthermore, EUS data can be used to identify all high-risk lesions. With these characteristics identified, clinicians are better able to risk-stratify patients using EUS as either appropriate for or too high-risk for endoscopic resection.

Endoscopic papillectomy: The limits of the indication, technique and results

In the majority of cases, duodenal papillary tumors are adenomas or adenocarcinomas, but the endoscopy biopsy shows low accuracy to make the correct differentiation. Endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography are important tools for the diagnosis, staging and management of ampullary lesions. Although the endoscopic papillectomy (EP) represent higher risk endoscopic interventions, it has successfully replaced surgical treatment for benign or malignant papillary tumors. The authors review the epidemiology and discuss the current evidence for the use of endoscopic procedures for resection, the selection of the patient and the preventive maneuvers that can minimize the probability of persistent or recurrent lesions and to avoid complications after the procedure. The accurate staging of ampullary tumors is important for selecting patients to EP or surgical treatment. Compared to surgery, EP is associated with lower morbidity and mortality, and seems to be a preferable modality of treatment for small benign ampullary tumors with no intraductal extension. The EP procedure, when performed by an experienced endoscopist, leads to successful eradication in up to 85% of patients with ampullary adenomas. EP is a safe and effective therapy and should be established as the first-line therapy for ampullary adenomas.

Endoscopic papillectomy: Indications, techniques, and results

Endoscopic papillectomy (EP) is currently accepted as a viable alternative therapy to surgery in sporadic ampullary adenoma and has been reported to have high success and low recurrence rates. At present, the indications for EP are not yet fully established. The accepted criteria for EP include size (up to 5 cm), no evidence of intraductal growth, and no evidence of malignancy on endoscopic findings (ulceration, friability, and spontaneous bleeding). Endoscopic ultrasound (EUS) is the imaging modality of choice for local T staging in ampullary neoplasms. Data reported in the literature have revealed that linear EUS is superior to helical computed tomography in the preoperative assessment of tumor size, detection of regional nodal metastases and detection of major vascular invasion. Endoscopic ampullectomy is performed using a standard duodenoscope in a similar manner to snare polypectomy of a mucosal lesion. There is no standardization of the equipment or technique and broad EP methods are described. Endoscopic ampullectomy is considered a ‘‘high-risk’’ procedure due to complications. Complications of endoscopic papillectomy can be classified as early (pancreatitis, bleeding, perforation, and cholangitis) and late (papillary stenosis) complications. The appropriate use of stenting after ampullectomy may prevent post-procedural pancreatitis and papillary stenosis. Tumor recurrence of benign lesions occurs in up to 20% of patients and depends on tumor size, final histology, presence of intraductal tumor, coexisting familial adenomatous polyposis (FAP), and the expertise of the endoscopist. Recurrent lesions are usually benign and most can be retreated endoscopically.