Atypical Burkitt Lymphoma

Comments:
In atypical (pleomorphic) Burkitt lymphoma, the tumor cells are larger in size and display pleomorphism. Gastrointestinal tract is less commonly involved (although the case shown here involved ileo-cecal junction) and bone marrow involvement is more frequent. The immunophenotypic and genotypic features are similar to those of classical Burkitt lymphoma. The 2008 WHO Classification recommends dropping the use of the term "Atypical Burkitt Lymphoma." This gross specimen shows infiltration of gut wall and the mesenteric fat by the lymphoma. The lymphoma cells were positive for CD20, CD10, bcl-6, and negative for bcl-2, TdT, and EBV associated nuclear antigen 1. Ki-67 proliferation index was 90-95%. The tumor was ileo-cecal. The patient was a 12 y/o male. Image copyright: pathorama.ch