Intraductal papillary mucinous neoplasm: clinical surveillance and management decisions

A Functional Spatial Analysis Platform for Discovery of Immunological Interactions Predictive of Low-Grade to High-Grade Transition of Pancreatic Intraductal Papillary Mucinous Neoplasms

Intraductal papillary mucinous neoplasms (IPMNs), critical precursors of the devastating tumor pancreatic ductal adenocarcinoma (PDAC), are poorly understood in the pancreatic cancer community. Researchers have shown that IPMN patients with high-grade dysplasia have a greater risk of subsequent development of PDAC in the remnant pancreas than do patients with low-grade dysplasia. In this study, we built a computational prediction model that encapsulates the spatial cellular interactions in IPMNs that play key roles in the transformation of low-grade IPMN cysts to high-grade cysts en route to PDAC. Using multiplex immunofluorescent images of IPMN cysts, we adopted algorithms from spatial statistics and functional data analysis to create metrics that summarize the spatial interactions in IPMNs. We showed that an ensemble of models learned using these spatial metrics can robustly predict, with high accuracy, (1) the dysplasia grade (low vs high grade) and (2) the risk of a low-grade cyst progressing to a high-grade cyst. We obtained high classification accuracies on both tasks, with areas under the curve of 0.81 (95% confidence interval: 0.71-0.9) for task 1 and 0.81 (95% confidence interval: 0.7-0.94) for task 2. To the best of our knowledge, this is the first application of an ensemble machine learning approach for discovering critical cellular spatial interactions in IPMNs using imaging data. We envision that our work can be used as a risk assessment tool for patients diagnosed with IPMNs and facilitate greater understanding and investigation of the cellular interactions that cause transition of IPMNs to PDAC.

Pancreatobiliary fistula associated with intraductal papillary mucinous carcinoma accompanying obstructive jaundice: A case report

INTRODUCTION

Intraductal papillary mucinous neoplasms (IPMNs) occasionally involve formation of fistulas with other adjacent organs. Pancreatobiliary fistulas associated with IPMNs are rare, but affected patients often develop obstructive jaundice and cholangitis.

PRESENTATION OF CASE

A 79-year-old man was referred to our hospital for evaluation of abnormal biliary enzymes. Contrast-enhanced computed tomography and endoscopic retrograde cholangiopancreatography demonstrated multiple cystic lesions with septa in the pancreatic head and fistulas between the cystic lesions and common bile duct. The clinical diagnosis was pancreatobiliary fistula associated with a mixed-type IPMN and accompanying obstructive jaundice. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy. The resected specimen showed fistulas between the cystic lesions and common bile duct. Histopathological examination showed that the main and branch ducts of the pancreatic head were dilated and filled with mucus. The epithelia of the pancreatic ducts revealed papillary proliferation and an invasive adenocarcinoma arising from an intraductal neoplasm. Immunohistochemistry examination showed CDX2- and MUC2-positive reactions. The final diagnosis was an intraductal papillary mucinous carcinoma of the intestinal-type. The patient remained disease-free for 9 months postoperatively.

DISCUSSION

The causes of death in patients who have pancreatobiliary fistulas associated with IPMNs without resection are cholangitis or hepatic insufficiency. Nonoperative treatment is limited for cases with obstructive jaundice. It is necessary to prevent obstructive jaundice and cholangitis due to a large quantity of mucinous material.

CONCLUSIONS

Surgical resection should be considered, if possible, in patients with pancreatobiliary fistulas associated with IPMNs. A better prognosis is expected with prevention of obstructive jaundice or cholangitis.

Prognostic value of histological subtype in intraductal papillary mucinous neoplasm of the pancreas: A retrospective analysis of outcome from one single center

We sought to retrospectively analyze the outcomes of patients with intraductal papillary mucinous neoplasm (IPMN) at our pancreatic surgery center, and to evaluate the prognostic value of histological subtype.The clinical data of 121 IPMNs treated in our center between 2005 and 2014 were retrospectively analyzed. Pathological slides were thoroughly reviewed by 2 specialized pathologists.Of the 121 patients, 48, 57, and 16 had main-duct, branch-duct, and mixed type IPMNs, respectively. Forty-one patients had invasive IPMNs. Histological subtypes consisted of 35 intestinal (28.9%), 56 gastric (46.3%), 29 pancreatobiliary (24.0%), and 1 oncocytic type (0.8%). Histological subtype was associated with radiological type, T stage, and degree of dysplasia (P < .05). No significant difference in overall survival was observed among the 4 histological subtypes, regardless of whether we considered all IPMNs (P = .106), or invasive IPMNs only (P = .828). However, the overall survival was associated with radiological type, T stage, degree of dysplasia, lymph-node status, and nerve invasion. For invasive IPMNs, the overall survival was associated with nerve invasion and lymph-node status; however, the association between nerve invasion and overall survival lost statistical significance after multivariate analysis.Histological subtype had limited prognostic value in patients with IPMNs, and the main prognostic factor for patients with invasive IPMNs was the lymph-node status.

Intraductal Papillary Mucinous Neoplasm of the Pancreas With High Malignant Potential on FDG PET/MRI

A 57-year-old man underwent FDG PET/CT to evaluate a mass in the head of the pancreas. The imaged revealed mildly, nonuniformly increased activity in the mass, but the exact location of the activity could not be determined on the low-dose noncontrast CT portion of the study. On subsequent PET/MRI images acquired 60 minutes after the FDG PET/CT study, the increased activity was clearly localized on the cystic wall. The pathological examination showed that the lesion was intraductal papillary mucinous neoplasm of the pancreas with high degree of dysplasia.

Interobserver agreement in the cytologic grading of atypia in neoplastic pancreatic mucinous cysts with the 2-tiered approach

BACKGROUND

The accurate cytologic grading of epithelial atypia in fine-needle aspirates of pancreatic mucinous cysts has important implications for clinical management. The Papanicolaou Society of Cytopathology has recommended a 2-tiered system of low-grade (LG) and high-grade (HG) for grading this atypia. Using this approach, this study examined the interobserver agreement within a group of cytopathologists at the Cleveland Clinic.

METHODS

Twenty cases of fine-needle aspiration of pancreatic neoplastic mucinous cysts with documented histologic follow-up and representative lesional cells were selected. Blinded to the histologic outcome, 4 cytopathologists were independently asked to assign the highest grade of atypia with the 2-tiered system of LG and HG atypia for these cases. The interobserver agreement was calculated with the κ statistic.

RESULTS

The overall raw agreement in the grading of atypia was 60%. The overall chance-adjusted agreement was fair (κ = 0.28). On the basis of the histologic outcomes, the cases were stratified into group A (HG dysplasia or worse) and group B (LG or intermediate-grade [IG] dysplasia on follow-up). Group A (n = 12) showed good chance-adjusted agreement (κ = 0.65). For group B, the chance-adjusted agreement among the observers was poor (κ = 0.03).

CONCLUSIONS

This study shows that the cytologic recognition of HG dysplasia or worse as HG atypia in pancreatic mucinous cysts has a good degree of interobserver reproducibility among cytopathologists. In contrast, a problematic area with a lack of agreement appears to be the cytologic recognition of LG and IG dysplasia as LG atypia. Additional studies with the development of reproducible criteria and educational tools may help with this challenging distinction. Cancer Cytopathol 2016;124:909-916. © 2016 American Cancer Society.

Surgical treatment and prognosis of 96 cases of intraductal papillary mucinous neoplasms of the pancreas: a retrospective cohort study

INTRODUCTION

The indications, the extent and type of surgery for intraductal papillary mucinous neoplasm (IPMN) are still controversial. This study aimed to investigate clinical manifestation, individualized surgical treatment, and prognosis of IPMN of pancreas.

METHODS

The clinical data of 96 IPMN cases treated in our hospital between January 2006 and December 2013 were retrospectively analyzed. Among the 96 patients (58 male and 38 female), 46 were main-duct type, 29 were branch-duct type, 21 were mixed type. Pancreatectomy was performed on 78 cases, including pancreaticoduodenectomy on 43 patients, distal pancreatectomy on 25, segmental pancreatectomy on 6, and total pancreatectomy on 4. A regular follow-up without surgical treatment was performed on 18 cases with asymptomatic side branch IPMN less than 3 cm in diameter.

RESULTS

The overall postoperative morbidity rate was 33.3%, and there was no perioperative mortality. 46 cases were non-invasive IPMN, 32 cases were invasive IPMN including 14 cases with lymph node metastasis. The five-year survival rate for patients with non-invasive and invasive carcinomas was 96.2% and 35.2%, respectively. The prognosis of invasive cases with lymph node metastasis was significantly worse than those without lymph node metastasis. No progression was found during the follow-up in 18 asymptomatic small branch duct type IPMN patients.

CONCLUSION

IPMN has a relative good prognosis. Main duct type and mixed type IPMN have a higher malignant potential, and should receive surgical treatment. Patients of branch duct type IPMN with lesion <3 cm in diameter and without clinical manifestations can be managed with close follow-up.

Endoscopic techniques for diagnosis and therapy of pancreatic intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a cystic neoplasm with potential malignancy. In the past, screening of IPMN depended on traditional imaging examinations, such as transabdominal ultrasonography and computed tomography (CT). With the development of endoscopic techniques, endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreatography (ERCP) and other endoscopic techniques are becoming significant diagnostic methods for IPMN. Meanwhile, endoscopic interventional therapy with the advantage of minimal invasiveness has been used to treat some patients who cannot tolerate or refuse surgery. This paper elucidates the advances in diagnosis and therapy of pancreatic IPMNs using endoscopic techniques.