Partial response to venetoclax and ruxolitinib combination in a case of refractory T-prolymphocytic leukemia.

T-prolymphocytic leukemia (T-PLL) is an aggressive hematologic malignancy. A portion of patients can be cured with alemtuzumab induction followed by allogeneic hematopoietic stem cell transplant, but patients who relapse after transplant have a poor prognosis, and there is no standard of care. We report a case of a 64-year-old man with relapsed JAK3-mutant T-PLL following allogeneic transplant who was treated with ruxolitinib and venetoclax. Treatment with ruxolitinib and venetoclax resulted in a partial response including stabilization of the peripheral lymphocyte count, improvement in thrombocytopenia, decrease in splenomegaly, and a numerical reduction in the percentage of bone marrow involved by T-PLL. The combination was well tolerated with the exception of neutropenic infections. This case adds to the growing body of literature supporting venetoclax and rituximab as a viable treatment option for relapsed/refractory T-PLL with JAK-STAT alterations.