[1657] Hepatobiliary Aggressive B Cell Lymphomas: Histologic, Immunohistochemical and Genetic Evaluation of a Large Series

Renuka Agrawal, Kate E Grimm, Lawrence Weiss, Dennis P O'Malley. Clarient Inc./GE Healthcare, Aliso Viejo, CA

Background: Diffuse large B cell lymphoma and related entities are the commonest type of non-Hodgkin lymphomas. Within this diagnosis are several distinct clinicopathologic entities. Lymphomas of the hepatobiliary tract are exceedingly rare and poorly studied. We evaluated a series of 449 aggressive B cell lymphomas and identified 12 cases involving the hepatobiliary tract.
Design: 449 cases were evaluated using an extensive panel of immunohistochemical stains (CD20, CD3, CD5, CD10, cyclin D1, bcl6, bcl2, EBER, Ki67, CD30) and a panel of FISH studies (including MYC, IGH/bcl2 and bcl6). Twelve cases (2.7%) were identified in the pancreas, liver and gallbladder.
Results: The majority of cases were diffuse large B cell lymphoma (DLBCL)(10/12; 83%) with two cases of Burkitt lymphoma identified (17%). The majority of cases (∼67%) were of germinal center origin by both Hans and tally classifiers. CMYC translocations were seen only in the BL, and no MYC-positive DLBCL or “double hit” lymphomas were identified. Compared to a large group of lymphomas from both the upper and lower gastrointestinal tract, hepatobiliary lymphomas were less often positive for BCL6 translocations (9% vs. 22%) and more often positive for IGH/BCL2 translocations (36% vs. 18%).
Conclusions: Our series shows that aggressive lymphomas are quite rare in the hepatobiliary tract. They show heterogeneity of immunophenotype and genetics. Hepatobiliary aggressive lymphomas have pathologic and genetic differences from those of the upper and lower GI tract as well as from nodal aggressive B cell lymphomas.
Category: Liver

Tuesday, March 5, 2013 9:30 AM

Poster Session III # 197, Tuesday Morning

 

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