La vitamine D et le risque du cancer du sein

Beaucoup de patients atteints de cancer du sein se tournent vers des thérapies médicales complémentaires, comme les antioxydants, les minéraux, les phytochimiques, les oméga 3, etc. Ces molécules présentent une option prometteuse pour la chimioprévention naturelle, sont moins toxiques et ont des propriétés antioxydantes et anti-inflammatoires. 
Aujourd'hui, on parle de la vitamine D et le risque du cancer:

• 6 études avec un nombre total de 5984 patients ont été identifiées.
• Au seuil de 23.3 nmol / L, pour un incrément de 10 nmol / L, 20 nmol / L ou 25 nmol / L dans les niveaux circulants de 25-OH-D, le risque de mortalité globale du cancer du sein a diminué de 6%, 12 % et 14%, respectivement.
• Les résultats suggèrent qu'il existe une relation dose-réponse linéaire très significative entre les niveaux circulants de 25-OH-D et la survie globale chez les patients atteints de cancer du sein.

LE CANCER DU SEIN: PLUS DE DÉTAILS...

RÉFÉRENCE
Veuillez lire l'article complet  (en anglais seulement) : 
Integr Cancer Ther. 2017 May 1:1534735417712007. doi: 10.1177/1534735417712007.
Circulating Vitamin D and Overall Survival in Breast Cancer Patients: A Dose-Response Meta-Analysis of Cohort Studies.Hu K1, Callen DF2, Li J1, Zheng H1.​
Abstract
Studies have shown that vitamin D could have a role in breast cancer survival; however, the evidence of the relationship between patients' vitamin D levels and their survival has been inconsistent. This meta-analysis explores possible dose-response relationships between vitamin D levels and overall survival by allowing for differences in vitamin D levels among populations of the various studies.
Studies relating vitamin D (25-OH-D [25-hydroxyvitamin D]) levels in breast cancer patients with their survival were identified by searching PubMed and Embase. A pooled HR (hazard ratio) comparing the highest with the lowest category of circulating 25-OH-D levels were synthesized using the Mantel-Haenszel method under a fixed-effects model.
A two-stage fixed-effects dose-response model including both linear (a log-linear dose-response regression) and nonlinear (a restricted cubic spline regression) models were used to further explore possible dose-response relationships. Six studies with a total number of 5984 patients were identified.
A pooled HR comparing the highest with the lowest category of circulating 25-OH-D levels under a fixed-effects model was 0.67 (95% confidence interval = 0.56-0.79, P < .001). Utilizing a dose-response meta-analysis, the pooled HR for overall survival in breast cancer patients was 0.994 (per 1 nmol/L), Pfor linear trend < .001.
At or above a 23.3 nmol/L threshold, for a 10 nmol/L, 20 nmol/L, or 25 nmol/L increment in circulating 25-OH-D levels, the risk of breast cancer overall mortality decreased by 6%, 12%, and 14%, respectively.
There was no significant nonlinearity in the relationship between overall survival and circulating 25-OH-D levels.
Our findings suggest that there is a highly significant linear dose-response relationship between circulating 25-OH-D levels and overall survival in patients with breast cancer.
However, better designed prospective cohort studies and clinical trials are needed to further confirm these findings.