Sustained response to erythropoietin for anemia in NK-cell large granular lymphocytosis: A brief case report

Large granular lymphocytic leukemia (LGL) is a rare lymphoproliferative disorder that involves the T-cell lineage in around 85% of cases and NK-cell lineage in 15%. Most patients require treatment at some point of their disease trajectory to address clinical symptomatology largely pertaining to cytopenia. While immunosuppression represents the backbone of LGL therapy, there is no consensus on the best next line following failure of immunosuppression. Here we present a case of LGL-associated cytopenia in a 73-year-old male refractory to immunosuppression, treated with adjunct erythropoietin alpha (EPO) with a marked response. Our case suggests that EPO therapy may provide therapeutic benefit in refractory LGL cases when used in conjunction with immunosuppressive therapy.