Higher vitamin D levels associated with lower tumor size and better overall survival in breast cancer patients.

Researchers collected serum from 1800 early breast cancer patients at diagnosis, measured 25-hydroxyvitamin D(3) (vitamin D) levels and determined genetic variants in vitamin D-related genes. The results showed that lower vitamin D levels significantly correlated with larger tumor size at diagnosis but not with lymph node invasion, receptor status, or tumor grade. Genetic variants in 25-hydroxylase (CYP2R1) and vitamin D-binding (DBP) protein significantly determined serum vitamin D levels but did not affect the observed association between serum vitamin D and tumor size. High serum vitamin D (>30ng/mL) at diagnosis significantly correlated with improved overall survival and disease-specific survival and additionally had a modest effect on disease-free interval, which only became apparent after at least 3 years of follow-up. When considering menopausal status, serum vitamin D had a strong impact on breast cancer-specific outcome in postmenopausal patients, whereas no association could be demonstrated in premenopausal patients. The authors conclude "high vitamin D levels at early breast cancer diagnosis correlate with lower tumor size and better overall survival, and improve breast cancer-specific outcome, especially in postmenopausal patients".

Hatse S, Lambrechts D, Verstuyf A, Smeets A, Brouwers B, Vandorpe T, Brouckaert O, Peuteman G, Laenen A, Verlinden L, Kriebitzsch C, Dieudonné AS, Paridaens R, Neven P, Christiaens MR, Bouillon R, Wildiers H. Vitamin D status at breast cancer diagnosis: correlation with tumor characteristics, disease outcome, and genetic determinants of vitamin D insufficiency. Carcinogenesis. 2012 Jul;33(7):1319-26.