title: Serum 25-hydroxyvitamin D levels and prognosis in hematological malignancies: a systematic review and meta-analysis.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  Low serum 25(OH)D levels are significantly associated with poorer prognosis in patients with hematological malignancies including lymphoma and leukemia.
authors: Department of Hematology, Affiliated Hospital of Qingdao University, Qingdao, China.
authors: Wei
authors: W
authors: Wang
authors: Guangyun
authors: G
authors: Li
authors: Xiaoyan
authors: X
authors: He
authors: Jian
authors: J
authors: Gao
authors: Robin
authors: R
authors: Wang
authors: Yangang
authors: Y
authors: Wang
authors: Wenjuan
authors: W
authors: Zhao
mesh_terms: D016208:Databases, Factual; D018572:Disease-Free Survival; D019337:Hematologic Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000401:mortality; D006801:Humans; D011379:Prognosis; D015996:Survival Rate; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D