ABSTRACT
New drugs for multiple myeloma (MM) have dramatically improved patients' overall survival (OS). Autologous stem cell transplantation (ASCT) remains the mainstay for transplant-eligible MM patients. To investigate whether the post-ASCT prognosis of MM patients has been improved by new drugs, we undertook a retrospective observational analysis using the Transplant Registry Unified Management Program database in Japan. We analyzed 7323 patients (4135 men and 3188 women; median age, 59 years; range 16-77 years) who underwent upfront ASCT between January 2007 and December 2018. We categorized them by when they underwent ASCT according to the drugs' introduction in Japan: group 1 (2007-2010), group 2 (2011-2016), and group 3 (2017-2018). We compared the groups' post-ASCT OS. The 2-year OS rates (95% confidence interval [CI]) of groups 1, 2, and 3 were 85.8% (84.1%-87.4%), 89.1% (88.0%-90.1%), and 92.3% (90.0%-94.2%) (P < .0001) and the 5-year OS (95% CI) rates were 64.9% (62.4%-67.3%), 71.6% (69.7%-73.3%), and not applicable, respectively (P < .0001). A multivariate analysis showed that the post-ASCT OS was superior with these factors: age less than 65 years, performance status 0/1, low International Staging System (ISS) stage, receiving SCT for 180 days or less post-diagnosis, better treatment response pre-ASCT, later year of ASCT, and receiving SCT twice. A subgroup analysis showed poor prognoses for the patients with unfavorable karyotype and poor treatment response post-ASCT. The post-ASCT OS has thus improved over time (group 1 < 2 < 3) with the introduction of new drugs for MM. As the prognosis of high-risk-karyotype patients with ISS stage III remains poor, their treatment requires improvement.