Leptin, insulin and body composition changes during adjuvant taxane based chemotherapy in patients with breast cancer, preliminary study.

BACKGROUND: The objectives of the present study were to compare the effect of adjuvant chemotherapy for breast cancer on serum insulin levels, serum leptin levels, and body composition in early stage breast cancer patients.
MATERIALS AND METHODS: 17 breast cancer patients underwent 6 cycles of docetaxel (75 mg), epirubicine (100 mg) and cyclophosphamide (500 mg) (TEC). Anthropometrical and foot-to-foot body fat analyzer BIA, serum glucose, insulin, lipids, HOMA-IR and leptin were compared pre- and post-treatment.
RESULTS: There was no statistically significant weight gain after treatment; however, there was an overall trend toward weight gain (69.7 ± 9.8 kg vs 71.03 ± 9.8; P= 0.05). From baseline to the end of the study, percentage of body fat and body fat mass showed an upward trend at the end of chemotherapy (1%; 2 kg P> 0.05). Pre and post-treatment period, leptin was strongly correlated with insulin and HOMA-IR (Spearman's pre-T; r = 0.74; P <0.001, r = 0.66; P = 0.004 post-T; r = 0.549; P =0.022, r = 0.51; P =0.036, respectively). Insulin levels were significantly increased in the post-treatment period (P < 0.05). On correlation analysis, post-T insulin levels were correlated with leptin, weight, fat-mass and fat percentage (Spearman's r = 0.549; P=.022, r = 0.567; P= 0.018, r = 0.498, P= 0.042, r = 0.502; P= 0.040, respectively). DISCUSSION: High insulin and leptin levels, important factors that were previously shown to be related to breast cancer outcome, and insulin resistance may be increased in taxane based chemotherapy regimen. These data may have broad implications for diet and lifestyle strategies for the prevention and treatment of cancers.