Yamashita T, Takamatsu H, Kawamura K, et al. - This study’s findings demonstrate that multimodal treatment including lenalidomide in addition to conventional intrathecal chemotherapy (IT) and radiation therapy (RTx) can improve overall survival (OS).

• Between 2005 and 2016, a total of the 77 adult patients with CNS-MM were distinguished, those diagnosed at MM diagnosis (n = 3) had longer overall survival than those diagnosed at relapse (n = 74; median: 48·5 vs 2·7 months).

• Researchers matched the relapsed MM with CNS-MM in patients with any treatment (n = 60).

• In this multivariate analyses, results demonstrated that lenalidomide treatment [hazard ratio (HR) 0·27, P = 0·003], intrathecal chemotherapy (IT; HR 0·54, P = 0·05), and radiation therapy (RTx; HR 0·33, P < 0·001) for CNS-MM had a positive effect on longer OS.

• These factors were applied to construct a scoring system combining the number of treatments with lenalidomide, IT, and RTx (0, 1, 2, 3).

• They stratified OS of CNS-MM patients based on these factors, with a median OS of 1·1, 4·5, and 7·5 months for patients with zero, one, two to three favorable features, respectively (0 vs 1, P = 0·0002; 1 vs 2–3, P = 0·08).