[Construction and Validation of a Multivariable Nomogram Model for Survival Prediction in Patients with Multiple...

To construct and validate a multivariable nomogram model for survival prediction in patients with multiple myeloma (MM) based on bone marrow flow cytometric immunophenotypes and peripheral blood inflammatory indices, so as to provide a tool for individualized prognostic assessment in clinical practice.

A total of 110 newly diagnosed MM patients admitted to the Department of Hematology of Xuancheng People's Hospital from January 2020 to June 2025 were retrospectively enrolled and randomly assigned (1∶1) to a training cohort (n=55) and a validation cohort (n=55) using a random number table method. Baseline clinical data and bone marrow flow cytometric expression of CD56, CD19, CD28 and CD117 were collected. The peripheral blood neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were calculated. Overall survival (OS) was defined as the primary endpoint. Univariate analysis was performed using the Kaplan-Meier method and log-rank test. Independent prognostic factors were identified by multivariate Cox proportional hazards regression in the training cohort, on the basis of which a nomogram was constructed. Model performance and clinical utility were evaluated by the concordance index (C-index), receiver operating characteristic (ROC) curves, calibration curves and decision curve analysis (DCA), and externally validated in the validation cohort.

By the end of follow-up, the median follow-up time was 32 months, and the median OS for the whole cohort was 41.5 months. Multivariate analysis showed that CD56 negativity, CD28 positivity, high NLR and low LMR were all independent adverse prognostic factors for OS (all P < 0.05). The nomogram constructed on these variables yielded a C-index of 0.78 in the training cohort, with area under the curve (AUC) values of 0.82 and 0.80 for 1-year and 3-year OS prediction, respectively. In the validation cohort, the C-index was 0.76, and the AUCs for 1-year and 3-year OS were 0.79 and 0.77, respectively. Calibration curves indicated good agreement between predicted and observed survival probabilities, and DCA suggested that the model provided substantial net benefit across a wide range of threshold probabilities.

Bone marrow plasma cell expression of CD56 and CD28, together with peripheral blood NLR and LMR, are important independent prognostic factors for survival in MM patients. The multivariable nomogram model based on these parameters shows good discrimination and calibration, and can accurately predict patient survival, thereby facilitating individualized risk stratification and treatment decision-making.