Site Editors
Shaji K. Kumar, MD
Prashant Kapoor, MD, FACP
Shaji K. Kumar, MD
Prashant Kapoor, MD, FACP
Posted: Wednesday, August 10, 2022
Total marrow irradiation during a second cycle of autologous stem cell transplantation (ASCT) may improve clinical outcomes for patients with multiple myeloma, according to a phase I/II study conducted by George Somlo, MD; Jeffrey Wong, MD; and colleagues at the City of Hope National Medical Center, Duarte, California. In fact, this treatment produced good response rates and reduced toxicity compared with total-body irradiation plus melphalan administration. The findings of this study were published in the journal Transplantation and Cellular Therapy.
“Total marrow irradiation as an ablative modality may represent a useful broad-spectrum tool in the context of current more effective induction and prolonged maintenance therapies and also offers the capability of boosting sites of interest, which could be of benefit in the setting of bulky or focally refractory disease,” stated the study investigators.
Patients with Salmon-Durie stage I to III multiple myeloma who had been diagnosed within 18 months and were now in response or with stable disease were enrolled. All patients received melphalan at 200 mg/m2 in conjunction with ASCT during the first cycle. Following recovery, one group of patients (n = 54) received a second cycle of ASCT concurrently with total marrow irradiation as the sole ablative modality. Other patients (n = 8) did not receive a second cycle.
The majority of patients received the maximum tolerated dose (1,600 cGy); the median time from melphalan administration to total marrow radiation was 65 days, and maintenance therapy was conducted for up to 1 year. Following treatment and maintenance, complete and very good partial response rates were observed in 70.3% of patients. The median follow-up was 12.3 years, and at 10 years, the rates of progression-free survival and overall survival were 20.4% and 38.8%, respectively. Tandem ASCT was well tolerated with limited toxicities, with the observed rates of solid tumors (5.5%) and acute myeloid leukemia (2%) comparing favorably with previous reports in the transplant settings for multiple myeloma.
Disclosure: For full disclosures of the study authors, visit astctjournal.org.
Transplantation and Cellular Therapy
