Metaplasia in the Gallbladder: An Analysis of Clinicopathologic Associations in 1218 Cholecystectomies.
Nevra Dursun, Juan Carlos Roa, Oscar Tapia, Olca Basturk, Sudeshna Bandyopadhyay, Asli Cakir, Michael Goodman, Juan Sarmiento, Hector Losada, NVolkan Adsay. Emory, GA; UFRO, Temuco, Chile; MSKCC, NY; WSU, MI
Background: There is conflicting data regarding the prevalence of intestinal and pyloric metaplasia (IM and PM) in the gallbladder (GB) and their association with GB carcinogenesis.
Design: The prevalence of IM and PM were analyzed in 1218 cholecystectomies from low vs high GB carcinoma (GBC) risk populations (US vs Chile; LR and HR), and non-neoplastic GBs vs dysplasia/early (mucosa confined) carcinomas vs advanced carcinomas. Length of mucosa examined from each case was recorded.
Results: Patients with metaplasia (mean age=55 yrs) were younger than those with GBC (mean=63; p<0.001). The frequency of both IM and PM was significantly higher in HR population (28% and 57%) than in LR population (12% and 45%; p<0.001). Moreover, the frequency of IM was significantly higher in neoplastic GBs (34%) than in non-neoplastic GBs (%10; p<0.001); however, intriguingly, the highest frequency was encountered in dysplasia/early GBCs (50%) vs advanced GBCs (27%) vs non-neoplastic GBs (10%), (p<0.001). All associations for IM were determined to be independent of sampling size (after adjusting for mucosal length by logistic regression analyses the p-values remained <0.001). By contrast, similar adjustment for PM attenuated the associations. Most IM was represented as goblet cells while the participation of absorptive cells/brush-border appeared to be very minimal. Areas with goblet cells often also showed significant atypia that qualify as dysplasia.
Conclusions: I. IM occurs in patients who are 5-10 years younger than those with carcinoma. II. While PM appears to be ubiquitous, IM is significantly more common in HR population, and in GBs with carcinomatous transformation supporting the role of IM as pre-precursors of carcinoma. III. Furthermore, IM is seldom seen in the absence of dysplastic changes and therefore it is advisable to sample/examine the cases with IM more closely. IV. That IM is more common in dysplasia/early GBC cases than advanced GBCs may suggest that early and advanced GBCs may not be a mere continuum but rather distinct processes as has been recently discovered in other organs, such as the sequence of athrophy-IM-invasive carcinoma in the stomach associated with intestinal subtype, which warrants further analysis.
Tuesday, March 1, 2011 1:00 PM
Poster Session IV # 70, Tuesday Afternoon