ABSTRACT
The aim of the study was to investigate whether microvessel density (MVD) could be associated with skeletal extramedullary disease relapse (skeletal-EMDR) in patients with multiple myeloma (MM) who have skeletal-EMD at diagnosis. Seventy-nine newly diagnosed MM patients who have skeletal-EMD were retrospectively enrolled in this study. The 4-year cumulative incidence of skeletal-EMDR was 35.0%±8.3%. The 4-year probability of overall survival (OS) was 54.0%±7.6%. Multivariate analysis showed that skeletal-EMDR (HR = 4.144; 95% CI: 1.608-10.685; P = 0.003) was independently associated with inferior OS for the MM patients who have skeletal-EMD at diagnosis. The factors associated with skeletal-EMDR were MVD (HR = 3.990, 95%CI:1.136-14.018; P = 0.031), white blood cell (WBC) (HR = 0.262, 95% CI:0.090-0.769; P = 0.015), and the EMD sites involved at onset (HR = 0.263, 95% CI: 0.074-0.937; P = 0.039). The MVD in patients with thoracic and lumbar vertebrae as the involved sites at diagnosis was significantly lower than those with other sites involved (41.59 ± 14.39 vs. 60.82 ± 35.14, P=0.001). Our data suggest that increased MVD could be used to predict skeletal-EMDR, which is associated with inferior survival in patients with MM who have skeletal-EMD at diagnosis.