Interdisciplinary management of an intraductal papillary mucinous neoplasm of the pancreas

Intraductal Papillary Mucinous Neoplasm of the Pancreas: Current Perspectives

In this article, we aimed to review the literature on the clinics and management of intraductal papillary mucinous neoplasm (IPMN). Intraductal papillary mucinous neoplasm of the pancreas is a mucin-producing cystic mass originating from the pancreatic ductal system. Approximately 25% of the pancreatic neoplasms resected surgically and 50% of pancreatic cysts detected incidentally are IPMNs. They can be benign or malignant in character, while malignant transformation of benign forms can be encountered. It is important to determine IPMNs in the early stages, implementation of appropriate treatment approaches, and follow-up to provide better prognosis. We reviewed the studies published in the English medical literature through PubMed and summarized the clinical features and current approaches to the treatment and follow-up of the IPMN. Due to the recent advances and widespread implementation of radiological imaging techniques, the incidental detection rate of IPMNs has increased significantly. The effective treatment of the disease is possible via the detailed diagnosis of the disease, determination of the prognostic factors, and a multidisciplinary approach. Recent literature also emphasized the molecular profile determination approaches for assessment of prognosis of patients with IPMN. Current knowledge on IPMN, a clinically important epidemiologic problem, shows that the treatment should be personalized considering the prognostic features and life expectancy of the patient.

Metabolic Activity by 18F-FDG-PET/CT Is Prognostic for Stage I and II Pancreatic Cancer

PURPOSE

Metabolic activity, as defined by F-FDG uptake on PET, is a prognostic marker for multiple malignancies; however, no study has examined the prognostic value of imaging with FDG PET in stage I and II pancreatic cancer. We examined the value of PET FDG uptake in early-stage pancreatic cancer patients.

METHODS

We identified patients with early-stage pancreatic cancer (I-II) who had FDG PET scan performed as part of their preoperative evaluation. The patients were divided into either high or low FDG uptake according to the median primary tumor standard uptake value (SUVmax). Our primary end points were overall survival (OS) and recurrence-free survival (RFS). Kaplan-Meier estimate was used for survival analysis. Pathologic data were compared using the Fisher exact and χ tests.

RESULTS

One hundred five patients were identified: 51 patients with low FDG uptake and 54 patients with high FDG uptake. Eighty-five patients (81%) had PET avid tumors, whereas 20 (19%) patients did not. High FDG uptake correlated with pathologic stage (P = 0.012). Patients with low FDG uptake had significantly better median OS than patients with high FDG uptake (28 vs. 16 months; P = 0.036). Patients with low-FDG uptake had significantly longer median RFS than patients with high FDG uptake (14 vs. 12 months; P = 0.049).

CONCLUSIONS

Low FDG uptake in PET scans in patients with stage I and II pancreatic cancer correlates with improved OS and RFS. This supports the concept that glucose metabolic pathways are important in pancreatic cancer biology and that PET scan activity can be used as a prognostic biomarker after pancreatectomy.

Endoscopic ultrasound-guided ablation of branch-duct intraductal papillary mucinous neoplasms: Feasibility and safety tests using porcine gallbladders

BACKGROUND AND AIM

Radiofrequency ablation (RFA) and ethanol ablation are accepted methods of tissue destruction for treating cystic tumors. The aim of the present study was to evaluate the feasibility, efficacy, and safety of endoscopic ultrasound (EUS)-guided ablation using normal porcine gallbladders as a substitute model for branch-duct intraductal papillary mucinous neoplasms (BD-IPMN).

METHODS

Six adult mini pigs were included in this prospective study. EUS-guided RFA with or without ethanol ablation of the gallbladder was carried out using a prototype 18-gauge endoscopic RFA electrode, and RFA and ethanol ablation were done in a single session. Outcomes were assessed in terms of macroscopic and microscopic evaluations of the treated gallbladders.

RESULTS

The prototype RFA electrode was used for ablation of the mucosa, aspiration of the internal contents of the gallbladder, and ethanol injection. RFA plus ethanol lavage resulted in a greater mean percentage of denuded gallbladder mucosa (97.5%) than RFA alone (55.8%). Effects of ablation extending to the cystic duct and partially denuded cystic duct mucosae were detected in five of the six pigs. There were no major procedure-related adverse events.

CONCLUSIONS

EUS-guided ablation of the gallbladder mucosa was feasible and effective in the porcine model. Additional studies will be required to fully assess the risk of procedure-related damage to the main pancreatic duct before using this technique in a clinical setting.

Prevalence, Diagnosis and Management of Pancreatic Cystic Neoplasms: Current Status and Future Directions

Cystic neoplasms of the pancreas are found with increasing prevalence, especially in elderly asymptomatic individuals. Although the overall risk of malignancy is very low, the presence of these pancreatic cysts is associated with a large degree of anxiety and further medical investigation due to concerns about malignancy. This review discusses the different cystic neoplasms of the pancreas and reports diagnostic strategies based on clinical features and imaging data. Surgical and nonsurgical management of the most common cystic neoplasms, based on the recently revised Sendai guidelines, is also discussed, with special reference to intraductal papillary mucinous neoplasm (IPMN; particularly the branch duct variant), which is the lesion most frequently identified incidentally. IPMN pathology, its risk for development into pancreatic ductal adenocarcinoma, the pros and cons of current guidelines for management, and the potential role of endoscopic ultrasound in determining cancer risk are discussed. Finally, surgical treatment, strategies for surveillance of pancreatic cysts, and possible future directions are discussed.

Extent of Surgery and Implications of Transection Margin Status after Resection of IPMNs

Appropriate surgical strategies for management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are a matter of debate. Preoperative and intraoperative evaluation of malignant potential of IPMN and of patient's comorbidities is of paramount importance to balance potential complications of surgery with tumors' risk of being or becoming malignant; the decision about the extent of pancreatic resection and the eventual total pancreatectomy needs to be determined on individual basis. The analysis of frozen-section margin of pancreas during operation is mandatory. The goal should be the complete resection of IPMN reaching negative margin, although there is still no agreed definition of “negative margin.” Of note, the presence of deepithelization is often wrongly interpreted as absence of neoplasia. Management of resection margin status and stratification of surveillance of the remnant pancreas, based on characteristics of primary tumour, are of crucial importance in the management of IPMNs in order to decrease the risk of tumor recurrence after resection. Although risk of local and distant recurrence for invasive IPMNs is increased even in case of total pancreatectomy, also local recurrence after complete resection of noninvasive IPMNs is not negligible. Therefore, a long-term/life-time follow-up monitoring is of paramount importance to detect eventual recurrences.

Preoperative evaluation and management of the pancreatic head mass

The differential diagnosis of a pancreatic head mass encompasses a wide range of clinical entities that include both solid and cystic lesions. This chapter focuses on our approach to the patient presenting with a newly found pancreatic head mass with the main goals of determining the risk of the lesion being malignant or premalignant, resectability if the patient is appropriate for surgical intervention, assessment of need for multimodality treatment and determination the patient's surgical risk.

[Differentiated therapy for intraductal papillary mucinous neoplasms]

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas are of increasing interest in the field of pancreatic surgery ever since their first description as an individual pancreatic tumor entity in 1982. The decision for surgical or conservative management is based on the adenoma-carcinoma sequence and the differentiation into main-duct or branch-duct IPMN. Invasive IPMN forms (carcinoma in situ and invasive carcinoma) and in particular noninvasive IPMNs (adenoma and borderline tumors) reveal significantly better survival rates than ductal adenocarcinoma of the pancreas.

A Case Report of Intraductal Papillary-Mucinous Neoplasm of the Pancreas Showing Morphologic Transformation during Followup Periods

A 64-year-old man underwent MRCP for further examination of gallbladder stones and IPMN of branch-type (IPMN-Br) was pointed out. Yearly MRCP had revealed the gradual increase of the cystic components, marked dilation of the main pancreatic duct (MPD), and filling defects in the MPD. After follow-up for three years, he underwent pancreatoduodenectomy. Histologically, the dilated MPD and connecting dilated branch ducts were filled with nodular growth of tumor cells consisting of gastric-type adenoma with pyloric gland-like structures. In the MPD, a transition from gastric-type adenoma to intestinal-type carcinoma was observed. In addition, in a dilated branch duct, some components of intestinal-type carcinoma with marked arborizing structures were observed. A minimally invasion was observed around branch ducts. Immunohistochemistry revealed diffuse nuclear accumulation of PCNA and Ki67 in the tumor cells of branch dusts. Our observations suggest that the secondary infiltration to the MPD of IPMN-Br and IPMN-Br possesses malignant potential for microinvasion.