title: Association between alterations in the serum 25-hydroxyvitamin d status during follow-up and breast cancer patient prognosis.
abstract: BACKGROUND
  Serum vitamin D status can affect the prognosis of breast cancer patients. Our aim was to determine the association between alterations in the 25-hydroxyvitamin D [25(OH)D] status during follow-up and the prognosis of breast cancer patients. Additionally, we evaluated the association between the 25(OH)D status at the time of diagnosis and the prognosis using a detailed age and stage categorization.
  
  
  METHODS
  Four hundred and sixty-nine Korean breast cancer patients were included. We collected patient clinicopathological data, including their serum 25(OH)D concentration at diagnosis and at the annual follow- up until 4 years after diagnosis. The patients were divided according to their 25(OH)D status at diagnosis into a deficient (<20 ng/ml) and a non-deficient (≥20 ng/ml) group. At follow-up, patients were categorized into the four following groups according to 25(OH)D status alterations: persistently deficient, improved, deteriorated and persistently non-deficient.
  
  
  RESULTS
  At diagnosis, 118 patients were classified into the deficient group and 351 into the non-deficient group. After a median follow-up period of 85.8±31.0 months, the patients with advanced- stage disease or an older age in the non-deficient group showed a significantly better survival compared with the deficient group. Furthermore, at the 1-year follow-up of 25(OH)D status, the persistently non-deficient group and the improved group had better survival compared with the other two groups.
  
  
  CONCLUSIONS
  Our results suggest that maintaining an optimal 25(OH)D status at diagnosis and during the 1-year follow-up period is important for improving breast cancer patient survival.
authors.affiliation: Department of Surgery, Division of Breast and Thyroid Surgical Oncology, St. Vincent's Hospital, The Catholic University of Korea, Suwon, Kyunggi-do, Korea E-mail : yjsuh@catholic.ac.kr.
authors.forename: Seung Taek
authors.initials: ST
authors.lastname: Lim
authors.forename: Ye Won
authors.initials: YW
authors.lastname: Jeon
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Suh
mesh_terms: D001943:Breast Neoplasms / Q000097:blood* / Q000175:diagnosis* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000401:mortality*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D