Second malignancies in total therapy 2 and 3 for newly diagnosed multiple myeloma: influence of thalidomide and lenalidomide during maintenance.

Thalidomide and lenalidomide constitute an important part of effective myeloma therapy. Recent data from the Intergroup Francophone du Myelome, Cancer and Leukemia Group B, and Gruppo Italiano Malattle Ematologiche dell Adulto MM-015 trials suggest that lenalidomide main-tenance therapy is associated with a higher incidence of second primary malig-nancies (SPMs), including both hemato-logic and solid malignancies. In the pres-ent study, we analyzed data from the Total Therapy 2 (TT2) trial, along with the 2 Total Therapy 3 (TT3) trials. TT2 patients were assigned randomly to either a con-trol group (no thalidomide) or to the ex-perimental group (thalidomide during in-duction, between transplantations, and during consolidation and maintenance). The 2 TT3 trials used thalidomide and bortezomib during Induction, before and in consolidation after tandem melphalan-based transplantation; TT3A applied VTD (bortezomib, thalidomide, dexametha-sone) in the first year of maintenance and TD for 2 more years, whereas TT3B used VRD (bortezomib, lenalidomide, dexa-methasone) maintenance for 3 years. The cumulative incidence of SPMs did not differ significantly among the TT trial com-ponents when measured from enrollment (P = .78) or from initiation of mainte-nance (P = .82). However, a palrwise com-parison of the TT2 arms suggested a lower incidence of hematologic SPMs in the thalidomide maintenance arm (hazard ratio = 0.38; P = .09). These trials are registered at www.clinicaltrials.gov as NCT00573391 (TT2), NCT00081939 (TT3A), and NCT00572169 (TT3B). [ABSTRACT FROM AUTHOR]