Adult Atypical Sporadic Burkitt Lymphoma Successfully Treated with Bendamustine and Rituximab

Sporadic Burkitt lymphoma (BL) accounts for 1% to 2% of lymphomas in adults. The abdomen is the most common site of involvement. The 2008 World Health Organization Classification of Tumors of Haematopoietic and Lymphoid Tissues introduced a new category of high-grade B-cell lymphomas: an entity with overlapping features of both diffuse large B-cell lymphoma and Burkitt lymphoma (DLBCL/BL). These lymphomas reportedly have poor overall survival rates. We present a case of an elderly adult atypical sporadic BL with jaw and bone marrow involvement. The tumor had the typical characteristic of BL including atypical monotonous lymphoid infiltrate with a starry-sky appearance and a high Ki67 proliferate index of 95%. MYC/IgH rearrangement was seen in 93.5% of the cells with 92% of cells also positive for IgH/Bcl-2, a feature of double-hit lymphoma. This atypical case of adult sporadic BL had features as classified of DLBCL/BL. Though high intensity regimen is used in BL and atypical BL, elderly patients tend to not tolerate these regimens well. Our patient was treated with bendamustine and bituximab given herelderly age and poor cardiac status. The patient responded well to chemotherapy and remains in complete remission two years after diagnosis up to the date of this report. The atypical presentation and excellent response to bendamustine plus rituximab has not been previously reported.