Mucin-producing neoplasms of the pancreas: an analysis of distinguishing clinical and epidemiologic characteristics

Abstract

Background & aims: Mucin-producing neoplasms (MPNs) of the pancreas include mucinous cystic neoplasms (MCNs) and main-duct, branch-duct, and combined intraductal papillary mucinous neoplasms (IPMNs). MCNs and branch-duct IPMNs are frequently confused; it is unclear whether main-duct, combined, and branch-duct IPMNs are a different spectrum of the same disease. We evaluated their clinical and epidemiologic characteristics.

Methods: Patients who underwent resection for histologically confirmed MPNs were identified (N = 557); specimens were reviewed and eventually reclassified.

Results: One hundred sixty-eight patients (30%) had MCNs, 159 (28.5%) had branch-duct IPMNs, 149 (27%) had combined IPMNs, and 81 (14.5%) had main-duct IPMNs. Patients with MCNs were significantly younger and almost exclusively women; 44% of patients with main-duct or combined IPMNs and 57% of those with branch-duct IPMNs were women. MCNs were single lesions located in the distal pancreas (95%); 11% were invasive. IPMNs were more frequently found in the proximal pancreas; invasive cancer was found in 11%, 42%, and 48% of branch-duct, combined, and main-duct IPMNs, respectively (P = .001). Patients with invasive MCN and those with combined and main-duct IPMNs were older than those with noninvasive tumors. The 5-year disease-specific survival rate approached 100% for patients with noninvasive MPNs. The rates for those with invasive cancer were 58%, 56%, 51%, and 64% for invasive MCNs, branch-duct IPMNs, main-duct IPMNs, and combined IPMNs, respectively.

Conclusions: MPNs comprise 3 different neoplasms: MCNs, branch-duct IPMNs, and main-duct IPMNs, including the combined type. These tumors have specific clinical, epidemiologic, and morphologic features that allow a reasonable degree of accuracy in preoperative diagnosis.

Conflict of interest statement

Conflicts of interest

The authors disclose no conflicts.

Copyright 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Examples of imaging of main-duct (A, B), branch-duct (C, D), combined IPMN (E), and MCN (F). (A) Endoscopic ultrasound features with mural nodule in a dilated MPD. (B) Main-duct IPMN at magnetic resonance cholangiopancreatography. (C) Branch-duct IPMN at endoscopic ultrasound. (D) Multifocal branch-duct IPMN at magnetic resonance cholangiopancreatography. (E) Radiologic features of combined IPMN at computed tomography scan. (F) Computed tomography features of an MCN.

Figure 2

Five-year disease-specific survival (DSS) comparing patients with noninvasive neoplasms including adenoma, borderline, and carcinoma in situ (black lines) and patients with invasive cancer (hatched lines) for different pancreatic MPNs. (A) DSS of 100% and 56% in noninvasive and invasive branch-duct IPMNs, respectively. (B) DSS of 95% and 51% in noninvasive and invasive main-duct IPMNs, respectively. (C) DSS of 100% and 64% in noninvasive and invasive combined IPMNs, respectively. (D) DSS of 100% and 56% in noninvasive and invasive branch-duct IPMNs, respectively.