An unusual case of hepatosplenic T cell lymphoma in a 59-year-old woman

Hepatosplenic T cell lymphoma (HSTL) is a rare aggressive T cell lymphoma which can be diagnostically challenging. We report a case of a 59-year-old woman presenting with sepsis, hepatosplenomegaly, ascites and multi-organ failure. The liver biopsy revealed active hepatitis and steatosis, additionally, with small numbers of atypical sinusoidal lymphoid cells, occasionally forming short chains, but without sinusoidal expansion, difficult to identify and partly masked by inflammatory changes. The cells showed CD3+, CD2+, CD5–, CD7–, CD4–/CD8–, CD56+, perforin+, TIA1+ and CD30+, suggesting an NK/T cell lymphoma, possibly HSTL, with peripheral T cell lymphoma, NOS, also considered. This prompted a subsequent bone marrow trephine, which contained a morphologically and immunophenotypically similar infiltrate of atypical lymphoid cells. Monoclonal TCR beta and gamma gene rearrangements were identified. Despite chemotherapy with CHOEP, the patient deteriorated rapidly and three months after initial diagnosis, she developed progressive CNS disease and died two weeks later. The liver and bone marrow findings, taken in conjunction with the clinical presentation including hepatosplenomegaly, absence of lymphadenopathy or atypical lymphoid cells in the blood, were considered most in keeping with HSTL. This case highlights the difficulty in diagnosis and appreciation of the neoplastic infiltrate of HSTL on haematoxylin-eosin stained slides, as the neoplastic infiltrate can be inconspicuous and masked by inflammatory changes. A high index of suspicion and low threshold for performing immunohistochemistry is prudent in such cases.