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 re-classified. 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.

Cystic Neoplasm of the Pancreas

“…MCNs occur almost exclusively in female, such as male cases are reported to be extremely rare [9][10]. The median age of presentation is reported to be 48 (range 16-82) and tumors are preferentially located in the body/tail of the pancreas [11,12]. Patients with malignant MCNs are typically older, suggesting a time-related degeneration of the tumor from an initially benign lesion.…”

“…We are nowadays aware that IPMNs are the most frequently detected pancreatic cysts, representing 39 % of the cystic surgical series [8]. Patients undergoing resection are typically in their sixth decade of life [11] with a slightly higher incidence for males. IPMNs can be either sporadic or associated with familial syndromes such as Peutz-Jeghers syndrome (PJS) and familial adenomatous polyposis (FAP).…”

“…If a clinical history of pancreatitis is present, a diagnosis of pseudocyst should be excluded, and in this scenario EUS can be beneficial [16,17]. Large surgical series have shown that the risk of invasive cancer for MCNs is 3.9-11 % and the 5-year disease-specific survival is 100 % and 58-62.5 % for non-invasive and invasive tumors, respectively [11]. In the last decades, when a MCN was suspected, indication to surgery was given by young patients' age because of the risk of progression to pancreatic cancer and by the relatively low morbidity associated to the distal resection of the pancreas [18].…”

Intraductal neoplasms of the pancreas: an update

“…However, survival outcomes are still favorable despite the second resection. Also, even though these intraductal neoplasms may develop invasive carcinoma, usually in the form of invasive oncocytic or mucinous (colloid-like) carcinoma, they still have more indolent course than conventional PDAC (16,31,38,40,71,121,124,126,133).…”

mAb Das-1 is specific for high-risk and malignant intraductal papillary mucinous neoplasm (IPMN)

“…We have shown that main-duct and mixed-type IPMNs are more likely to have invasive carcinoma compared with branchduct type (48% and 42% vs 11%) and, subsequently, 5-year disease specific survival rates of main-duct and mixed-type IPMNs are significantly lower than that of branch-duct type (65% and 77% vs 91%). 5 Histologically, IPMN is thought to progress from low-grade dysplasia (adenoma) to intermediate-and high-grade dysplasia (carcinoma in situ) and invasive carcinoma. 36 While the 5-year survival of patients with resected non-invasive IPMN is as high as 77%-94%, invasive IPMN carries a poorer survival of 33%-43%.…”