Clinical outcomes and prognostic factors in patients with multiple myeloma in South Tyrol: a retrospective single-center analysis.

High-dose chemotherapy followed by autologous stem cell transplantation (HD-ASCT) as well as the introduction of novel agents (NA) significantly improved survival for patients with multiple myeloma (MM). A total of 150 unselected newly diagnosed MM patients treated at our institution from 1998 to 2017 were retrospectively analyzed. Median age at diagnosis was 69 years (range 33-93 years) with a median follow-up of 48.6 months. The median overall survival (OS) for the entire cohort was 60.7 months (range 0.3-280.1). Patients who received frontline HD-ASCT (p < 0.01) or NA-based first-line treatment (p = 0.043) had a significantly better OS. According to the revised Myeloma Comorbidity Index (R-MCI), patients were defined as fit (36.5%), intermediate-fit (44.5%), or frail (19%) with a significant difference in OS between these categories (p < 0.01). Multivariate analysis revealed R-MCI as an independent prognostic factor for OS (p < 0.01). Presence of subclinical amyloid deposits (A+) was detected in 18 out of 66 patients (27.3%) and significantly correlated with a serum free light chain (sFLC) ratio ≥ 100 (p = 0.01) and bone marrow plasma cell infiltration > 60% (p = 0.04). Furthermore, patients with A+ had significantly worse OS compared with their counterparts (p = 0.048). Our results corroborate the efficacy of both early HD-ASCT and the use of new agents as initial therapy of MM patients in "real-world" daily clinical practice. The R-MCI is an easily applicable tool to stratify MM patients and may support treatment decisions. The prognostic value of subclinical amyloid deposition should be validated within prospective studies.