Vitamin D levels and breast cancer characteristics: Findings in patients from Saudi Arabia.

Inverse relationship between vitamin D status and risk of breast cancer has been previously reported in the literature. We conducted this study to determine the association between vitamin D levels and breast cancer characteristics in patients from Saudi Arabia. Newly diagnosed breast cancer patients (N=406) were recruited. Serum levels of 25-hydroxyvitamin D [25 (OH) D] were measured at baseline. A significantly higher percentage of patients with triple negative status (18%) had 25 (OH) D levels ≤25nmol/L, compared to only 8% with 25 (OH) D levels >25nmol/L (p=0.009). Patients with 25 (OH) D levels ≤25nmol/L were 2.54 times more likely to present with triple negative status compared to those with 25 (OH) D levels >25nmol/L (p=0.02). Our findings suggest an association between low 25 (OH) D levels and increased risk of triple negative breast cancer.