Impact of 1q gains on treatment outcomes of patients with newly diagnosed multiple myeloma in a real-world Swedish population receiving modern treatment.

Abstract

Amplification of 1q (amp(1q); ≥4 1q copies) has repeatedly been reported to predict a worse outcome in multiple myeloma (MM), whereas the impact of gain of 1q (gain(1q); three 1q copies) is less clear. We investigated survival of MM in relation to amp(1q) and gain(1q) by retrospectively analysing 346 consecutively newly diagnosed MM (NDMM) patients. Of these, 62 (18%) had amp(1q), 97 (28%) gain(1q) and 187 (54%) a normal number of 1q copies (no1q). The patients with amp(1q) had a shorter median progression-free survival than those with gain(1q) or no(1q) (13.1 months, 95% confidence interval [CI] 8.2-18.1 months vs. 36.1 months, 95% CI 23.1-49.1 months vs. 25.4 months, 95% CI 19.8-31.1 months, p = .005). The 3-year overall survival (OS) was 56% for amp(1q), 76% for gain(1q) and 80% for no1q (p = .003). In the multivariate analysis, the presence of amp(1q) was independently associated with a shorter OS (hazard ratio 1.99, 95% CI 1.03-3.82, p = .039), whereas gain(1q) had no negative effect on survival. Our results thus suggest that amp(1q) should be considered a high-risk abnormality in NDMM and that new treatment strategies should be explored to mitigate its negative effect on survival.