Abstract:
Objective To assess the efficacy, progression-free survival (PFS), and safety of liposomal doxorubicin (LPD) in patients with relapsed/refractory multiple myeloma (RRMM) with secondary extramedullary disease (sEMD) and evaluate overall survival (OS) and prognostic factors after the emergence of sEMD in patients with RRMM.
Methods Medical records of patients with RRMM were retrospectively analyzed. Forty patients with sEMD were treated with LPD in Beijing Chao-Yang Hospital from January 2015 to January 2020. The baseline characteristics of patients with an initial diagnosis of RRMM and clinical manifestations of sEMD were recorded. Moreover, efficacy, PFS, and safety of LPD were assessed. Furthermore, the OS after sEMD (sEMD-OS) was compared based on sEMD characteristics, and prognostic factors of sEMD-OS were determined using multivariate analyses.
Results International stage system stage (ISS) Ⅲ was confirmed as a risk factor for sEMD. All 40 patients completed a median of 5(3-9) treatment courses, with an overall response rate (ORR) of 60% after two cycles. Thirteen patients completed six or more treatment courses, with an ORR of 100%. The rate of adverse events above grade three was 5%. The estimated median PFS (mPFS) of LPD was 8.0 (95%CI: 7.5-8.5) months. PFS was superior in the group of LPD ≥6 cycles compared to that in the group of LPD <6 cycles after the landmark analysis (P=0.093). The estimated median sEMD-OS was 22.0 (95%CI: 18.2-25.8) months, with the 1- and 2-year OS rates being 73.6% and 38.2%, respectively. Extraosseous sEMD and lactate dehydrogenase (LDH) >250 U/L were confirmed to be independent prognostic factors.
Conclusions LPD-based regimens have good short-term efficacy and high tolerance in the treatment of RRMM with sEMD. Extraosseous sEMD and/or LDH>250 U/L indicates poor prognosis.