Novel insights into the early histopathogenesis of immunodeficiency-associated Burkitt lymphoma: a case report of Burkitt microlymphoma arising within HIV lymphadenitis.

To report a case detailing the early histopathogenesis of Burkitt lymphoma (BL), Epstein-Barr virus (EBV) positive, in the clinical setting of HIV infection.We describe a 57 year-old woman with newly diagnosed HIV infection who presented with unilateral localized axillary lymphadenopathy. Histopathological, immunohistochemical, and flow cytometric analyses were performed and showed EBV-positive nests of Burkitt cells, including rare nests also positive for cytomegalovirus, exclusively located within hyperplastic monocytoid B-cell areas of HIV lymphadenitis. Due to positron emission tomography/computed tomography findings of persistent localized lymphadenopathy with markedly increased fludeoxyglucose avidity a core needle biopsy was performed. Histopathological, immunohistochemical, fluorescence in situ hybridization, and flow cytometric analyses confirmed BL.Early histopathogenesis of HIV-associated BL occurred as nests of EBV-positive Burkitt cells within prominent monocytoid B-cell areas in our case. The results equip the pathologist to identify a very subtle Burkitt microlymphoma which would allow for prompt and appropriate chemotherapeutic intervention and may promote research into the possible relationship between monocytoid B cells and BL.