Peripheral Absolute Lymphocyte Count: An Economical and Clinical Available Immune-Related Prognostic Marker for Newly Diagnosed Multiple Myeloma.

BACKGROUND To find economical and clinically available immune-related prognostic markers that could predict the overall survival (OS) of newly diagnosed multiple myeloma (NDMM) in the new drug era. MATERIAL AND METHODS Absolute lymphocyte count (ALC) and absolute monocyte count (AMC) were measured in routine blood samples from 102 patients with NDMM, and the lymphocyte-monocyte ratio (LMR) was derived. All the patients were receiving bortezomib-based chemotherapy as induction treatment. Log-rank testing was used for comparing the differences between groups. Univariate and multivariate tests were used to identify prognostic markers. RESULTS The median ALC and LMR values at diagnosis were 1.43×10⁹/L and 3.7, respectively, and served as the cutoff point. As prognostic factors, ALC, LMR, and a new staging system combining ALC and the ISS staging system (L-ISS) were expected to have a significant impact on predicting OS. Furthermore, multivariate analysis showed that ALC ≥1.43×10⁹/L (hazard ratio [HR]: 0.223; 95% confidence interval [CI]: 0.071-0.705; P=0.011), LMR ≥3.7 (HR: 0.363; 95% CI: 0.139-0.947; P=0.038), and L-ISS late stage (HR: 1.619; 95% CI: 1.065-2.743; P=0.027) were independent predictors for OS. CONCLUSIONS ALC and LMR can serve as surrogate markers for patients' antitumor immunity at the initial diagnosis of multiple myeloma. A new immune-related staging system, L-ISS, which combines ALC and the ISS staging system, can predict clinical outcomes in patients who are receiving bortezomib-based chemotherapy.