AUTOLOGOUS STEM CELL TRANSPLANTATION IN ELDERLY MULTIPLE MYELOMA PATIENTS

Autologous stem cell transplantation (ASCT) is currently approved as a “gold standard” first line treatment for multiple myeloma (MM) patients (pts) under 65 years old but the procedure could also be considered feasible in fit elderly patients based on several retrospective studies. We retrospectively analyzed 25 consecutive MM pts aged 65 or older (median age 67, range 65-70) who underwent upfront ASCT at our institution from January 2012 to June 2016. The induction therapy was bortezomib-based (bortezomib in combination with dexamethasone, VD, in 7 or VD plus thalidomide in 18 pts) for a median of 4 cycles (range 3-6). Peripheral blood stem cells (PBSC) were collected after high-dose cyclophosphamide (3 g/sqm in 10 pts, 4 g/sqm in 15 pts) plus G-CSF, with plerixafor in 4 pts. Three pts also received lenalidomide and dexamethasone to improve the depth of response before ASCT. At the time of conditioning 4/25 pts were in partial response (PR), 14/25 in very good partial response (VGPR), 5/25 in complete response/stringent complete response (CR/sCR) and 2/25 in stable disease (SD). The conditioning regimen consisted of melphalan at 140 mg/sqm in 10 pts or 200 mg/sqm in 15 pts. A median number of 4.26 x10ˆ6 CD34+ cells/Kg was transplanted (range 2.09-10.44). The most frequent complication was fever (5 pts) with gram negative bacteriemia documented in 3 of 5. Other complications were represented by one case of atrial fibrillation and one case of pneumonia. All 25 pts achieved neutrofils recovery after a median of 12 days (range 8-25) and platelets recovery after a median of 14 days (range 8-45) after transplant. No grade 3-4 toxicities were recorded. No trasplant-related mortality was recorded at 100 days post transplantation. Three months after ASCT, among 22 evaluable pts, 7/25 pts were in CR, 11/25 pts in VGPR and 4/25 pts in PR. One patient underwent tandem ASCT. Three patients received lenalidomide maintenance after ASCT. After a median follow-up of 28 months (range 5-58) 13/25 pts experienced disease relapse. Nineteen of 25 were still alive. Median PFS and OS were 19 and 39 months. Our data support the use of ASCT as an effective and safe first-line treatment approach also in elderly MM pts. A careful patient selection is needed to reduce the toxicity of the procedure.