The impact of estrogen depletion by aromatase inhibitors on adiponectin serum levels in postmenopausal patients with breast cancer.

e11601 Background: Adiponectin impacts on breast cancer risk and prognosis. Obesity and insulin resistance are correlated with low adiponectin serum levels, which increase breast cancer risk and lead to a worse outcome regarding breast cancer. Additionally a cross talk between the adiponectin and estrogen signaling system has been suggested. Here we prospectively investigated the impact of estrogen depletion via aromatase inhibitors (AI) on adiponectin serum levels in postmenopausal patients with breast cancer. Methods: 68 postmenopausal ER positive patients with breast cancer, scheduled to receive anastrozole or letrozole as adjuvant endocrine treatment were prospectively included in this study. Serum was taken before (T1) and 3 months after start with aromatase inhibitors (T2). Non-fasting serum levels of adiponectin, FSH, LH, E2, glucose and insulin were analyzed immediately in the clinical routine lab and in a dedicated central lab able to measure E2 in serum at low concentrations with high sensitivit...