Plasma insulin-like growth factor in primary breast cancer patients treated with adjuvant chemotherapy

Insulin-like growth factor 1 (IGF-1) plasma level was assayed in 60 breast cancer patients undergoing six courses of adjuvant chemotherapy. The only observed variation was a slight decrease (10%) in IGF-1 concentrations, assayed before treatment, between the first and the second courses of chemotherapy. During chemotherapy courses, there were no statistically significant variations in IGF-1. These results suggest that chemotherapy, unlike the specific hormonal treatments tamoxifen and somatostatin, certainly does not act via a decrease in plasma IGF-1.