Four hepatosplenic T-cell lymphoma cases of Japanese patients

• Three out of four HSTCL cases in a Japanese institute were over 59 years of age.
• None of the patients had previous illness that was related to immunodeficiency.
• There may be a certain proportion of HSTCL patients who presented after middle age.

Hepatosplenic T-cell lymphoma (HSTCL), a rare type of γδ T-cell lymphoma, is characterized by hepatosplenomegaly and cytopenias. It is associated with immunodeficiency and its age of onset is reportedly between the 20s and 30s. We herein report 4 Japanese HSTCL cases. Three of them, including an elderly case that was 74 years of age, were not at adolescence. No cases had a history of immunodeficiency. All other disease phenotypes were similar to the typical HSTCL cases. These findings suggest that there are a certain proportion of HSTCL patients who presented after middle age.