Mucinous Carcinoma (MC) of the Gallbladder (GB): Clinicopathologic Analysis of 14 Cases Identified among 606 GB Carcinomas
O Tapia, JC Roa, A Cakir, N Dursun, I Coban, O Basturk, J Cheng, J Sarmiento, H Losada, NV Adsay. U de La Frontera, Temuco, Chile; Emory U, GA; NYU, NY
Background: There is virtually no data in the literature regarding the incidence, subtypes & clinicopathologic characteristics of MC of GB.
Design: 606 primary invasive GB carcinomas were reviewed. Extracellular mucin production of variable degrees & patterns was identified in 40(6%). Those with >50% of the tumor showing stromal mucin deposition (14 cases, 2.3%) were classified as MC. Remainders (26 cases, 3%) were excluded as adenocarcinoma with focal mucinous differentiation.
Results: Clinical: Mean age=64. F/M=1.6 (vs 3.8 of usual GB carcinomas; UCa). Pathology: Mean & median tumor sizes were larger than those of UCas (4.8 & 3.4 vs 2.7 & 2.4 cm, respectively; p=0.034). MCs revealed 3 histologic patterns: I.Colloid(2/14): >90% composed of well-defined stromal mucin nodules, some containing scanty ca cells, mostly floating within the mucin. II.Mixed-mucinous(7/14): Substantial amount (up to 50%) of other Ca component in addition to at least 50% mucinous pattern. III.Mucinous signet-ring cell(5/14): Both the cells within the mucinous component and those infiltrating into the stroma (individually or in cords) are mostly of signet-ring morphology. 3/14 MCs were associated with an intramucosal papillary neoplasm of villous-intestinal pattern. IHC: MCs lacked the gastric-pancretobiliary differentiation marker(MUC6) and some of the intestinal differentiation markers(CDX2/CK20); although colloid marker(MUC2) was expressed.
|4/7||2/7; F||3/7||6/7||6/7||0/7||1/7 F||3/7 (1; F)|