NGS-based monitoring of secondary acute lymphoblastic leukemia dynamics following lenalidomide maintenance in multiple myeloma patients.

We report on a series of three patients diagnosed with secondary acute lymphoblastic leukemia (sALL) following treatment for multiple myeloma (MM) where serial, commercially available, next-generation sequencing (NGS) based tracking of measurable residual disease (MRD) using the clonoSEQ assay provided valuable clinical insight. Each of the patients in this series had been treated for their MM with regimens that had included autologous stem cell transplantation following high dose melphalan chemotherapy and had been on maintenance treatment with the immunomodulatory drug lenalidomide for at least one year.