Three Cases of Lenalidomide Therapy for Multiple Myeloma and Subsequent Development of Secondary B-ALL.

The mechanism of lenalidomide associated SPMs is not well understood however its incidence is well documented. At least 13 cases of ALL (predominantly B-cell ALL) following Immunomodulator imide drugs (IMiDs) have been reported in literature. An analysis of a larger cohort of patients is required to determine causality of lenalidomide with sALL. However, benefits of maintenance lenalidomide in patients with MM outweighs the risk of developing SPMs. Albeit persistent pancytopenia on lenalidomide therapy should be evaluated with bone marrow biopsy since it could be caused by secondary B -cell ALL.