Minimally Invasive Intraductal Papillary-mucinous Carcinoma of the Pancreas: Clinicopathologic Study of 104 Intraductal Papillary-mucinous Neoplasms

Abstract

Invasive intraductal papillary-mucinous carcinoma (I-IPMC) is a heterogeneous entity with various postoperative outcomes. The aim of this study is to characterize early-stage I-IPMC with nonaggressive characteristics. One hundred and four patients with intraductal papillary-mucinous neoplasm (IPMN) were clinicopathologically investigated. The lesions were classified into 53 noninvasive IPMNs (adenoma, borderline, and noninvasive IPMC) and 51 I-IPMCs on the basis of the WHO classification. I-IPMCs were divided further into 26 minimally invasive IPMCs (MI-IPMCs) and 25 invasive carcinomas originating in IPMC (IC-IPMCs) by new diagnostic criteria proposed in this study. We examined invasiveness of I-IPMC on 4 patterns, and defined simple and practical diagnostic criteria of minimal invasion for each invasive pattern. The disease-specific survival rates after 3, 5, and 10 years were 100%, 100%, and 100% for both noninvasive IPMN and MI-IPMC, and 51%, 38%, and 0% for IC-IPMC. The overall and disease-specific survival rates for MI-IPMC were both significantly better than those for IC-IPMC (P<0.001), but there was no significant difference between noninvasive IPMN and MI-IPMC. Multivariate analysis showed that the factors indicative of poor prognosis were a diagnosis of I-IPMC classified as IC-IPMC and a high level of serum carbohydrate antigen 19-9. The prognosis of IC-IPMC was not significantly different from that of pancreatic ductal carcinoma in each of the corresponding tumor-node-metastasis stages. These findings suggest that a category of MI-IPMC provides more accurate and useful information of the stage and the aggressiveness of I-IPMC.

Prognosis of invasive intraductal papillary mucinous neoplasms of the pancreas

“…Colloid carcinoma is generally identified in association with intestinal-type IPMN and tubular carcinoma is generally found in association with pancreatobiliary IPMN [9] . Immunohistochemical studies have identified differences in the expression of the glycoproteins, MUC1, MUC2 and CDX2, between invasive colloid and tubular carcinoma IPMN, further suggesting that these entities are distinct from a molecular standpoint [10][11][12] . Colloid carcinoma associated with IPMN generally expresses both MUC2 and CDX2, markers of intestinal differentiation, a characteristic of more indolent carcinomas [13] .…”

Stromal thrombospondin-1 expression is a prognostic indicator and a new marker of invasiveness in intraductal papillary-mucinous neoplasm of the pancreas

“…A half of surgically resected IPMNs are intraductal papillary-mucinous adenoma (IPMA) or borderline IPMN even under current international criteria (21), and it is still unclear when they change to noninvasive intraductal papillary-mucinous carcinoma (IPMC), how long IPMC retains a status of "carcinoma in situ", and when IPMC achieves invasiveness. Particularly, invasive carcinoma originating from intraductal papillary-mucinous carcinoma (IC-IPMC) showed similar malignant behavior compared with conventional invasive ductal carcinoma both clinically and histologically (15). Minimally invasive IPMC (MI-IPMC) has been categorized within the classification of pancreatic carcinoma used by pancreatic IPMNs at Tokai University Hospital, Japan.…”

Factors in Intraductal Papillary Mucinous Neoplasms of the Pancreas Predictive of Lymph Node Metastasis

“…Among them, 2 patients without mural nodules had invasive carcinomas; however, both of them were minimally invasive carcinomas defined by Nara et al [10] as within 5 mm invasion to the pancreatic parenchyma. They reported that minimally invasive IPMNs are associated with no LNM and a 100% disease-specific survival rate [10]. Thus, lymph node dissection might be able to be diminished during pancreatectomy for IPMNs without mural nodules.…”