Primary bone marrow lymphoma is a rare neoplasm with poor outcome: case series from single tertiary care centre and review of literature.

Primary bone marrow lymphoma is a rare disease and remains undiagnosed due to deceptive clinical presentation. Here, we report four cases of primary bone marrow B-cell non-Hodgkin lymphoma, which presented with cytopenias without any lymphadenopathy or organomegaly. Bone marrow examination revealed large atypical B-cells with a reactive T-cell infiltrate with suppression of the normal hematopoietic elements. This lymphoma is known to have a poor prognosis. Inspite of treatment, two of our patients died during chemotherapy. Two patients relapsed, of which one showed an early relapse after two months and was put on an alternative regimen. The other patient relapsed twice at an interval of 4 and 5 years, respectively, following which he remained in remission for another 5 years and had recently shown a relapse for the third time. Review of literature revealed seven case series and 11 case reports of primary bone marrow lymphoma in the last five decades.