Serum 25-Hydroxyvitamin D Levels and Prognosis in Hematological Malignancies: A Systematic Review and Meta-Analysis

Background/Aims: Serum 25-hydroxyvitamin D [25(OH) D] levels proved to be associated with prognosis of patients with colorectal cancer or breast cancer, but its prognostic role in hematological malignancies was still unclear. A systematic review and meta-analysis was performed to comprehensively evaluate the association between serum 25(OH) D levels and prognosis of patients with hematological malignancies. Methods: We searched Pubmed, Embase, Web of Science, and Google Scholar for studies evaluating the association between serum 25(OH) D levels and prognosis of patients with hematological malignancies. The hazard ratios (HR) with 95% confidence intervals (95% CI) for overall survival (OS) or relapse-free survival (RFS) were pooled using meta-analysis. Results: Seven studies with a total of 2,643 patients with hematological cancer were finally included into the meta-analysis. Overall, compared with normal serum 25(OH) D levels, low serum 25(OH) D levels were significantly associated with both poorer OS (HR = 1.85, 95% CI 1.54-2.23, P < 0.001) and poorer RFS (HR = 1.45, 95% CI 1.25 to 1.70, P < 0.001) in hematological malignancies. Subgroup analysis further showed that low serum 25(OH) D levels were significantly associated with poorer OS and RFS in both lymphoma and leukemia. Conclusion: Low serum 25(OH) D levels are significantly associated with poorer prognosis in patients with hematological malignancies including lymphoma and leukemia. Copyright (C) 2015 S. Karger AG, Basel