Single versus double autologous stem cell transplantation and lenalidomide maintenance versus no maintenance therapy in newly-diagnosed patients with multiple myeloma: a real-life, vintage snapshot after twenty-three years from the Rete Ematologica Pugliese.

Autologous stem cell transplantation (ASCT), doubled in selected cases, followed by lenalidomide maintenance (LM) remains the standard treatment after induction therapy for newly diagnosed, transplant eligible patients with multiple myeloma (TEMM). Notwithstanding, evidences about how these approaches have been applied and how they have performed in the real-life setting, before the introduction of daratumumab within the induction regimens, are quite limited. Herein, we report the outcome of 300 MM patients, who underwent single (45%) or double (55%) ASCT, and received (42%) or not (58%) lenalidomide maintenance, outside of clinical trials, between December 2001 and February 2020, within the "Rete Ematologica Pugliese". After a median follow-up of 65 months (range: 9-186), median PFS was significantly longer in patients who underwent double ASCT compared to those who received single ASCT (66 vs. 53 months, respectively, p = 0.01). Likewise, after a median follow-up of 62 months (range: 9-174), patients who received LM had a significantly better PFS respect to those who did not (72 vs. 36 months, respectively p < 0.001). Concerning OS, it was not influenced by single or double ASCT (although a trend favoring double ASCT was observed), while LM significantly improved OS (142 vs. 108 months, p = 0.01). At multivariable analysis factors influencing PFS were achievement of complete remission after first ASCT, double ASCT and LM, while those impacting on OS were high risk cytogenetics, LDH and LM. In the context of a rapidly changing therapeutic scenario, our data might contribute to a real-life, historical benchmark for current and future treatments of TEMM patients.