Clinicopathological Features of Intraductal Papillary Mucinous Neoplasms of Pancreas in a Tertiary Care Center: A 14 Year Retrospective Study

Abstract

Introduction: Pancreatic surgeries are usually performed for inflammatory conditions and neoplasms. Intraductal Papillary Mucinous Neoplasm (IPMN) account for approximately 5-7% of all pancreatic neoplasms in western literature. To the best of our knowledge, there has been no published literature in Indian subcontinent on IPMN.

Aim: To assess the spectrum of different pancreatic pathologies on pancreatic resection specimens. Also, to review and share the experience on the clinicopathological features of IPMNs in our institute.

Materials and methods: This was a 14 year retrospective study of all cases where pancreatic surgeries were done for pancreatic pathology. The slides and blocks of diagnosed cases of IPMNs were retrieved from the department archives, reviewed and a detailed study on the histopathological features was done.

Results: Among the 377 pancreatic surgical specimens, pancreatitis was the most common diagnosis followed by exocrine neoplasms and endocrine neoplasms. IPMN constituted 3.2 % of all pancreatic neoplasms. Histologically, the most common type was the gastric foveolar type. Pancreatobiliary type was aggressive and associated with an invasive component and had evidence of metastasis on follow up.

Conclusion: IPMNs are rare neoplasms of pancreas with a male predominance. They are usually indolent except for the pancreatobiliary type which may have an aggressive course, often associated with an invasive adenocarcinoma component. Diligent follow up is recommended.

Keywords: Dysplasia; Gastric; Intestinal; Pancreaticobiliary.

[Table/Fig-5]:

a. Whipple specimen with a multiloculated mucin filled cystic tumour containing mural nodule located in the head of pancreas. b. Distal pancreatectomy and splenectomy specimen with a cystic tumour in the tail of pancreas (red arrows). The main pancreatic duct is mildly dilated (blue arrows).

[Table/Fig-6]:

IPMN, gastric foveolar type with low grade dysplasia. a. Dilated duct lined by mucinous columnar epithelium with a basally located uniform nuclei resembling gastric foveolar cells. H&E x100. b. The cells containing abundant mucin. d-PAS x100.

[Table/Fig-7]:

Intraductal papillary mucinous neoplasm (IPMN), intestinal type with intermediate grade dysplasia. a. Duct lined by villiform structures lined by columnar epithelial cells with occasional admixed goblet cells. H&E x100. b. Columnar epithelial cells with moderately pleomorphic nuclei, prominent nucleoli and displaying occasional mitotic activity. H&E 200x. c. Columnar epithelial cells with admixed goblet cells. d-PAS x200.

[Table/Fig-8]:

IPMN, pancreatobiliary type with high grade dysplasia. a. Duct with complex papillary and tubular structures lined by columnar epithelial cells. H&E 100x. b. Columnar epithelial cells lined by moderately pleomorphic nuclei displaying loss of polarity, stratification and frequent mitosis (red arrows). H&E 400x