Late extramedullary recurrence of adult onset Burkitt's lymphoma mimicking peritoneal carcinomatosis
Authors: Preetesh Jain, Ohad Benjamini, Ellen Schlette, Deborah A. Thomas, Susan O'Brien
Journal: American Journal of Hematology (2013)

A 46-year-old male presented with fatigability and night sweats in 2005. His physical examination was unremarkable. He had anemia, low platelets, and 47% circulating lymphoid cells. A bone marrow (BM) aspirate showed 91% lymphoid cells. These lymphoid cells were small-to-medium sized with a high nuclear/cytoplasmic ratio, dispersed nuclear chromatin, and finely vacuolated intensely basophilic cytoplasm (Image 1A-oil Wright Giemsa; 500× magnification). BM biopsy shows sheets of lymphoid cells, shown in (Image 1B-Hematoxylin and eosin (H&E); 500× magnification). Lymphoid cells expressed CD19, CD20, CD10, HLA-DR, Ki-67 (100%), Bcl6, Pax5, CD38, and monoclonal lambda light chain and were negative for TdT, Myeloperoxidase (MPO), and Bcl2. Cytogenetic analysis of the BM demonstrated t(8;14) (q24.1;q32) and fluorescent in situ hybridization (FISH) analysis was positive for C-MYC gene rearrangement. Cerebrospinal fluid (CSF) showed WBC of 15 cells/µL and 63% lymphoid cells. Serology for HIV was negative. He was diagnosed with Burkitt's leukemia (BL) with BM and asymptomatic central nervous system (CNS) involvement and received chemo-immunotherapy with rituximab and hyper-cyclophosphamide, vincristine, adriamycin, and dexamethasone (CVAD) with intrathecal methotrexate. He received a total of eight cycles of R-hyper-CVAD regimen. The patient completed therapy and was in complete remission (CR). In 2012, he presented to the emergency room with shortness of breath, fatigue, night sweats, and abdominal distention. He had bilateral pleural effusions and ascites but no lymphadenopathy or hepatosplenomegaly. The WBC was 8.4 K/µL, hemoglobin 10.3 g/dL, and platelet count 64 K/µL. There were no circulating lymphoid cells. Ascitic fluid cytology was positive for atypical lymphocytes of Burkitt's lymphoma with monoclonal kappa light chains (by flow cytometry), and Ki-67 (>95%) by immunocytochemistry. Biopsy of the mesenteric mass revealed atypical lymphocytes that were medium sized with oval to irregular nuclei, fine chromatin, inconspicuous nucleoli, and scant to moderate amounts of cytoplasm (Image 1C-oil Wright Giemsa; 500× magnification). Flow cytometry of cells from the mesenteric mass were similar to ascitic fluid. A FISH analysis on the mesenteric tissue was positive for c-MYC gene rearrangement (Image 1D). Pleural fluid cytology was negative for malignant cells. CSF analysis and BM were normal. Whole body positron emission tomography (PET) computerised tomography (CT) scan showed moderate ascites and intense curvilinear activity along the anterior abdomen, consistent with omental tumor, similar to peritoneal carcinomatosis (Image 1E). The patient was started on R-Etoposide, Vincristine, Doxorubicin, Cyclophosphamide, and Prednisone (EPOCH) treatment, consisting of rituximab, doxorubicin, vincristine, etoposide, cyclophosphamide, and prednisone. PET-CT scan at the end of the first cycle showed remarkable improvement in the mesenteric mass and ascites (Image 1F). The patient completed eight cycles of R-EPOCH and 12 courses of maintenance chemotherapy and remains in CR 10 months after relapse. Adult onset BL is a highly curable disease 1. The diagnostic hallmarks of BL are the presence of atypical lymphoid cells with CD20, CD19, CD10, Ki-67, and sIgM positive cells negative for Bcl2 and TdT and FISH positive for c-myc gene. Late relapses in adult BL have rarely been described 2. In the present case the signs of BL at the second presentation closely mimicked peritoneal carcinomatosis, both clinically and radiologically. As the expression of monoclonal light chains was different at the time of initial presentation (lambda) and at the recurrence (kappa), we hypothesize that this patient might have a clonally unrelated second Burkitt's lymphoma 3 or light chain switching in the same lymphoma clone 4, that is, true extramedullary recurrence of the original lymphoma. P.J., O.B., E.S., D.T., and S.O.B. gathered data and organized the images. P.J., O.B., and E.S. collected pictures and evaluated the pathology. All authors have reviewed the manuscript.