The relationship between breast cancer treatment, tumour type and vitamin D level in pre- and postmenopausal women.

Objective: Vitamin D deficiency has been linked to a higher risk of cancer. There is insufficient data regarding the influence of treatment on vitamin D status. The aim of this study was to compare pre- and post-treatment levels of 25(OH)D in premenopausal and postmenopausal women with breast cancer with a different receptor status (ER-estrogen receptors, PR-progesterone receptors) and in healthy controls.