Impact of high-risk cytogenetics and prior therapy on outcomes in patients with advanced relapsed or refractory multiple myeloma treated with lenalidomide plus dexamethasone

This retrospective analysis investigated the prognostic value of del(13) and t(4;14) abnormalities and the impact of prior treatment on outcomes in 207 heavily pretreated patients with relapsed or refractory multiple myeloma (MM) treated with lenalidomide plus dexamethasone. Patients with relapsed or refractory MM who had either earlier received thalidomide or bortezomib, or for whom continuation of these agents was contraindicated, and who had fluorescence in situ hybridization data available were included in the analysis. Patients with relapsed or refractory MM who received treatment with lenalidomide plus dexamethasone in the presence of del(13) and t(4; 14) chromosomal abnormalities had lower overall response rates (ORRs) and shorter median progression-free survival (PFS) and overall survival (OS) compared with those who did not have these abnormalities. The results also showed that prior treatment with bortezomib was associated with shorter median PFS and OS. Progression during thalidomide therapy was the only significant independent predictor for OS and that the presence of del(13) and hemoglobin levels <10 g per 100 ml were prognostic factors for ORR and PFS, but not OS, in these heavily pretreated relapsed or refractory MM patients treated with lenalidomide plus dexamethasone. Leukemia (2010) 24, 623-628; doi:10.1038/leu.2009.273; published online 14 January 2010