Presentation on theme: "Intraductal Papillary Mucinous Neoplasm (IPMN) of the Pancreas: it’s Histopathologic Difference Between 2 Major Types Shinichi Ban, MD,* Yoshihisa Naitoh,"— Presentation transcript:
1 Intraductal Papillary Mucinous Neoplasm (IPMN) of the Pancreas: it’s Histopathologic Difference Between 2 Major TypesShinichi Ban, MD,* Yoshihisa Naitoh, MD,* Mari Mino-Kenudson, MD, Takaki Sakurai, MD, Makoto Kuroda, MD,J Isamu Koyama, MD, Gregory Y. Lauwers, MD, and Michio Shimizu, MD*Am J Surg Pathol 2006, November ;Vol. 30: 1561–1569指導老師:方嘉郎；報告人:李俊志
2 IntroductionIPMN is characterized by a predominantly noninvasive growth pattern with mucin production and cystic duct dilatation.The distinction between IPMN and pancreatic intraepithelial neoplasia (PanIN),which is the common precursor of invasive carcinomas
3 Introduction 1999, Yonezawa Villous dark cell type--- resembles colorectal villous; MUC2 (+); intestinal typePapillary clear cell type--- resembles gastric foveolar epi. MUC (-); gastric typegastric type have not been fully described.
5 IntroductionGOALS:Evaluate the distribution of the IPMNs and their derived invasive carcinomasRefine their differences of gastric-type and intestinal-type--- regard to their histopathologic characteristics and mucin profilesBetter characterize the gastric type
6 Materials and Methods Patients’ data--- 80 cases: M/F(49/31) Mean age(65.3y/o, 37-83y/o);From1983 to 2003;from 4 hospitals (Saitama Medical School, Japan; Kyoto University Hospital, Japan; Fujita Health University, Japan, and Massachusetts General Hospital, USA)Exclusion: IPMNs of other type (ex:pancreatobiliary,oncocytic) and IPMN-like lesions
7 Materials and Methods based on WHO classification on tumors of the digestive systeminternational consensus guidelines for IPMN and mucinous cystic neoplasms (MCNs)Gastric type--- clear/lightly eosinophilic; columnar; round to ovoid nuclei; no/minimal pseudostratifiedIntestinal type--- dark eosinophilic; columnar; oval to spindle nuclei; pseudostratified
8 Materials and Methods Evaluation of 8 histologic features: distribution--- main duct or branch ducthistologic grade---benign/borderline/noninvasiveintraluminal nodular growthpyloric glandlike structureslow-grade PanIN-like complex within the tumor,atrophy of the surrounding pancreas tissuemucous lake formationoccurrence of invasive carcinoma.
9 B. main duct-type IPMN A. branch duct-type IPMN intraluminal nodular growthatrophy of the surrounding pancreas tissue with fibrosismucous lakes devoid of neoplastic cells
10 A, benign(hyperplasia) B, borderline;C, noninvasive carcinoma (high-grade dysplasia)Benign-borderlineBorderline-noninvasive
11 A. Pyloric glandlike: 2-3 glands lined by clear columnar epi A. Pyloric glandlike: 2-3 glands lined by clear columnar epi., located at the base of papillaB. PanIN-like complex: collection of small ducts lined by tall columnar mucinous cell
12 Materials and Methods Mucin profiles (Semiquantitative) Extent of staining(extent score)--- 0(no staining), 1(<1/3 positive), 2(1/3-2/3 positive), and 3(>2/3 positive)intensity of staining (intensity score)---0(no staining), 1(weak), and 2(strong).labeling score--- extent score+ intensity score
13 Results no significant difference between gender and age. Number GENDER: M/FMEAN AGEGASTRIC TYPE5031/1965.5 (47-83)INTESTINAL TYPE3018/1265.1(37-81)no significant difference between gender and age.
20 Discussion Larger main duct-type (73%) + Rare (3%) (33%) high (50%) Intra-luminal nodular growthLow grade PanIN complexPyloric gland-likestructuregradeatrophy and fibrosisMucous lakeinvasiveIntestinal typeLarger main duct-type (73%)+Rare(3%)(33%)high(50%)7/30(23%)Gastric typeBranch duct-type(98%)rare(82%)(96%)low1/50(2%)
21 DiscussionIntestinal-type IPMNs MUC2(+), whereas most gastric-type IPMNs are not.MUC5AC--- Both(+) in papilla, like organoid differentiation in stomach and pancreas.MUC6, both (+) ; more frequent in pyloric glandlike structures of gastric typeMUC1--- a marker for aggressiveness. both (-)--- IPMNs progress slowly
22 Discussion Malignant change: intestinal >gastric Mucin pools --- associated with mucinous adenocarcinoma in intestinal-type IPMNs; lead to muconodular infiltration, like occurred in invasive colorectal villous tumors; sign of invasiveGastric-type IPMNs--- conventional type
23 Discussion Gastric-type IPMNs V.S Low-grade PanIN Both have “pyloric gland-like structures” and “low-grade PanIN-like complex”Both are MUC5AC+/MUC2-Both have genetic alterantions associated with ductal carcinoma, ex: K-ras, p53, DPC4/Smad4, p16 (more common in Low-grade PanIN)Low-grade PanIN gastric-type IPMNsFurther molecular studies still needed
24 Discussion Two hypothesis Gastric type, which being called “null-type” by Adsay et al, may progress to intestinal type or othersDifferent phathogenesis between the two types different mode of spreading through the pancreatic ductal systemGastric type --- low-grade PanIN-like complexIntestinal type --- involving small ducts with complete atrophy of surrounding parenchyma