e18210 Background: Although many studies have investigated the association of blood 25OH-vitamin D (vit-D) levels with breast cancer prognosis, the results have been mixed. It has been suggested that low vit-D concentrations were associated with advanced tumor stage and triple-negative (TNBC) subtype. We retrospectively investigated associations of serum vit-D levels with triple negative breast cancer outcome. Methods: Out of 797 cases of TNBC diagnosed at William Beaumont Hospital between 2006-2017, 163 patients had vit-D level available within 1 year prior to diagnosis. Analyses of vit-D levels was classified by 3 cut points (deficient, < 20.0 ng/mL; insufficient, 20.0-29.9 ng/mL; sufficient, ≥30.0 ng/mL). Primary outcomes are disease free survival (DFS) and overall survival (OS). SPSS statistics 25 software was used to analyze the data. Results: Median age of diagnosis of TNBC was 60. Of these patients 43.6% were diagnosed with stage I, 37.4% at stage II, 4.9% at stage III and 4.9% at stage IV. 47.2% of the patients had sufficient vit-D level prior to diagnosis, 28.2% with insufficient vit-D level and 24.5% with deficient vit-D. Vit-D deficiency was more prevalent in premenopausal than in postmenopausal women (33.3%, 41% and 25.6% in premenopausal women for deficient, insufficient and sufficient levels respectively vs 21.8%, 24.2% and 54% in postmenopausal women). Rates of Vit-D deficiency were not different between early disease and advanced disease (24.3% of patient with stage I-II vs 25% in patients with stage III-IV). Median OS and disease-free survival were not statistically different among the 3 different categories. 5-year OS was 91%, 91% and 85% for deficient, insufficient and sufficient levels respectively. 5-year DFS was 93%, 95% and 95% for deficient, insufficient and sufficient levels respectively. Multivariate COX regression analysis demonstrated that age and stage were associated with mortality, whereas vit-D level was not. Conclusions: The results from this study show that adequate vit-D level do not have an impact on OS and DFS in patients with triple negative breast cancer. Premenopausal women are more likely to have inadequate vit-D level. Identification and treatment of vitamin D deficiency is still important for musculoskeletal health and possibly extraskeletal health in general population and breast cancer survivors specifically.
Effect of Capecitabine Maintenance Therapy Using Lower Dosage and Higher Frequency vs Observation on Disease-Free Survival Among Patients With Early-Stage Triple-Negative Breast Cancer Who Had Received Standard Treatment
