A third autologous stem cell transplantation (ASCT) is feasible and provides clinical benefit to patients with relapsed multiple myeloma, according to findings from a retrospective study.
The benefits appear to be most pronounced in patients who had a long duration of response to the previous ASCT, the researchers wrote in Biology of Blood and Marrow Transplantation.
“A salvage third ASCT is of value for patients with relapsed multiple myeloma,” Laurent Garderet, MD, of the department of hematology, Hôpital Saint Antoine, Paris, and coauthors wrote in the report.
A third transplantation is most commonly used in patients who relapse following tandem ASCT. Less often, it is done in patients who receive upfront ASCT, relapse, undergo a second ASCT, and relapse again.
“The first scenario gives much better results, due in part to a better remission status at the third ASCT with no signs of increased [second primary malignancy],” the researchers wrote.
In that group, median overall survival was greater than 5 years if the relapse occurred 3 years or more after the initial tandem ASCT, study results show.
The retrospective analysis, based on European Society for Blood and Marrow Transplantation data, included 570 patients who had undergone a third ASCT between 1997 and 2010. Of that group, 482 patients (81%) received the third transplantation after tandem ASCT and subsequent relapse, and 88 (15%) received it after second relapse.
After third ASCT, overall survival was 33 months in the larger tandem transplant group with 61 months of follow-up, and 15 months in the smaller group of patients who received two salvage ASCTs after 48 months of follow-up.
Median progression-free survival was 13 and 8 months for the tandem ASCT and two-salvage–ASCT groups, respectively, while 100-day nonrelapse mortality was 4% and 7%, respectively.
For both groups, better outcomes were associated with longer duration of remission after the second ASCT, the researchers reported.
Moreover, the time from second ASCT to relapse was the only favorable prognostic factor associated with survival after third ASCT in a multivariate analysis of the patients who relapsed following tandem transplant. The hazard ratio for relapse occurring between 18 and 36 months vs. within 18 months was 0.62 (95% confidence interval, 0.47-0.82; P = .01); for relapse after 36 months, the HR was 0.35 (95% CI, 0.25-0.49; P less than .001).
The researchers acknowledged that, beyond transplant, treatment of myeloma has changed substantially in recent years and could change the clinical picture for patients undergoing a third ASCT.
“The availability of novel agents may further improve the response to a third ASCT, rather than impairing its usefulness in the salvage setting, by enhancing the depth of response before ASCT, which could result in improved durability of the outcome,” they wrote.
The researchers reported having no financial disclosures related to this study.
SOURCE: Garderet L et al. Biol Blood Marrow Transplant. 2018 Feb 3. doi: 10.1016/j.bbmt.2018.01.035.
