ECTS2013 Poster Presentations Cancer and bone: basic, translational and clinical (31 abstracts)
1IMIM (Hospital del Mar Medical Research Institute), RETICEF, Barcelona, Spain; 2Internal Medicine Department, Hospital del Mar, Autonomous University of Barcelona, Barcelona, Spain; 3Breast Cancer Unit, Medical Oncology Department, Hospital del Mar, Autonomous University of Barcelona, Barcelona, Spain; 4Nuffield Department of Orthopaedics, IDIAP Jordi Gol Primary Care Research Institute, Autonomous University of Barcelona, Rheumatology and Musculoskeletal Sciences, Oxford NIHR Musculoskeletal Biomedi, London, UK; 5Cancer Research Program, IMIM (Hospital del Mar Research Institute), Barcelona, Spain; 6Laboratori de Referència de Catalunya, Barcelona, Spain; 7Department of Genetics, University of Valencia, Valenia, Spain; 8Department of Pediatrics, Obstetrics and Gynecology, University of Valencia, Valencia, Spain.
Background: Besides the classic actions of vitamin D on bone metabolism and calcium homeostasis, there is evidence emphasizing its antiproliferative and proapoptotic activities. Data coming mostly from Northern regions suggest an effect of 25-hydroxyvitamin D (25(OH)D) serum concentrations on breast cancer prevention. We aimed to study the association between 25(OH)D concentrations and breast cancer risk in a Mediterranean population (Spain).
Methods: We conducted a casecontrol study including 468 cases of early breast cancer and 280 cancer-free postmenopausal women (controls). Vitamin D deficiency was defined as serum 25(OH)D<30 ng/ml. Multivariable adjusted odds ratios (ORs) for the association between serum 25(OH)D levels (and deficiency) and breast cancer were calculated using logistic regression models, adjusted for age, BMI and season at blood collection. An a priori defined interaction with age was tested by introducing a multiplicative term in the logistic equation.
Results: Mean±S.D. serum 25(OH)D concentrations were lower in breast cancer cases compared to controls (17.3±9.8 vs 24.0±8.4 ng/ml, P<0.001). A significant association between 25(OH)D and risk of postmenopausal breast cancer was found: adjusted OR for vitamin D deficiency was 3.02 (1.90 to 4.86) (P<0.001). The corresponding adjusted OR for 25(OH)D concentration was 0.93 (0.91 to 0.94) (P<0.001) per each ng/ml increment in serum 25(OH)D. A borderline interaction between age and 25(OH)D (P=0.05) was detected. When stratified by median age we found an OR of 3.30 (1.71 to 6.46) among the older (aged 60 years or above), compared to an OR of 2.87 (1.50 to 5.68) for those aged <60 years.
Conclusions: Our results suggest an inverse association between 25(OH)D serum levels and early breast cancer prevalence among postmenopausal women from a Mediterranean region. In our data, vitamin D deficiency is related to an almost three-fold higher risk of breast cancer.