Concomitant intraductal papillary mucinous neoplasm and neuroendocrine tumor of the pancreas

Abstract

Abstract. Intraductal papillary mucinous neoplasm (IPMN) and neuroendocrine tumor (NET) of the pancreas are rare tumors and their association is not expected to be frequent. However, certain studies have suggested that the concomitant occurence of these tumors may be more frequent than previously thought. In the current study, we describe a case of concomitant occurrence of IPMN and NET of the pancreas and review the clinicopathological features of previously published cases and the current one. A 68-year-old female was incidentally found to have dilatation of the main pancreatic duct. A distal pancreatectomy was performed under the clinical diagnosis of IPMN. Histopathological analysis revealed concomitant IPMN (low-grade) and NET G1 of the pancreas. Review of the clinicopathological features of the 15 previously reported cases of concomitant IPMN and NET of the pancreas as well as the present one indicated that: i) this condition mainly affects middle-aged females; ii) the main symptom is abdominal or back pain, or no symptoms; iii) a hormone production symptom was observed in only one case; iv) the most common degree of dysplasia of IPMN is low grade; and v) the size of the NET is not particularly large (average 15.1 mm), although the clinical behavior is not always indolent (metastasis was observed in 3 cases). It is well known that IPMNs are associated with a high incidence of extrapancreatic malignancies, including colorectal and gastric carcinomas. Concomitant pancreatic NET and extrapancreatic malignancies may occur, therefore, systemic surveillance of extrapancreatic neoplasms and detection of concomitant NETs of the pancreas are necessary for patients with IPMN. IntroductionIntraductal papillary mucinous neoplasm (IPMN) is a rare intraductal epithelial neoplasm composed of mucin-producing cells arising in the main pancreatic duct or its branches (1). IPMNs are estimated to account for 1-3% of exocrine pancreatic neoplasms and 20% of all cystic neoplasms of the pancreas, and the incidence of this disease is considered to be increasing (1). The subtypes of IPMNs are recognized as main-duct and branch-duct types by macroscopic examination, and noninvasive IPMNs are classified into three categories on the basis of cytoarchitectural atypia: low-, intermediate-and high-grade dysplasia (1).Pancreatic neuroendocrine neoplasms are uncommon and represent 1-2% of all pancreatic neoplasms (2). According to the recent World Health Organization Classification of the Digestive System, neuroendocrine neoplasms are classified into three categories: neuroendocrine tumor (NET) G1 and G2 and neuroendocrine carcinoma (NEC; NET G3) (2).IPMN and NET of the pancreas are rare tumors and their association is not expected to be frequent. However, certain studies have suggested that the concomitant occurrence of these tumors may be more frequent than previously thought (3). In the current study, we describe a case of concomitant occurrence of IPMN and NET of the pancreas, and review the clinicopathological features of previously ...

The Clinical Utility of a Novel Blood-Based Multi-Transcriptome Assay for the Diagnosis of Neuroendocrine Tumors of the Gastrointestinal Tract

“…Whereas neuroendocrine features are uncommon in IPMNs ( 44 ), these precancerous lesions can coexist with NETs in ~3-5% of cases (45)(46)(47), not dissimilar to the current series (2/31 IPMNs exhibited an elevated NETest). Th e latter is an interesting "false positive" as previous histopathological studies have indicated that IPMNs and NETs can occur in adjacent areas of the pancreas ( 48,49 ). Such lesions are rarely functional and have a relatively small size (~1.5 cm), raising the possibility that additive information from a blood biomarker test may be of some clinical utility.…”

Pathologic Evaluation and Reporting of Intraductal Papillary Mucinous Neoplasms of the Pancreas and Other Tumoral Intraepithelial Neoplasms of Pancreatobiliary Tract

“…97, 178–181 Although neuroendocrine tumors can occur synchronously with IPMNs, it is much more common to see a non-neoplastic aggregation of the islets of Langerhans secondary to long-standing duct obstruction. 182–185 This latter finding should not be over-diagnosed as “islet cell hyperplasia,” or as a neuroendocrine neoplasm.…”

Synchronous pancreatic tumors in a patient with history of Wilms tumor: A case of pancreatic adenocarcinoma and lipid‐rich neuroendocrine tumor diagnosed by cytopathology

“…1,2 The relatively common synchronous tumors in the pancreas are the combination of intraductal papillary mucinous neoplasm (IPMN) and NET. [10][11][12][13][14][15][16][17] Serous cystadenoma is occasionally found as a component of pancreatic synchronous tumors. [18][19][20][21][22] Only a few cases mentioned the constitution of an adenocarcinoma in synchronous pancreatic tumors.…”