Impact of central obesity on prognostic outcome of triple negative breast cancer in Chinese women

Purpose: To evaluate the prognostic effect of central obesity on triple negative breast cancer (TNBC). Methods: 206 TNBC patients treated from June 2006 to June 2015 were enrolled retrospectively. Body mass index (BMI) >= 25 kg/m(2) was the standard of obesity and waist circumference >= 80 cm was the standard of central obesity. Patient and tumor characteristics were compared between obesity categories. Survival differences between obesity categories were assessed with log-rank test in the univariate analysis and prognostic factors were then investigated by Cox regression analysis. Results: 81 cases were with obesity (39.3 %). 71 cases were with central obesity (34.5 %). Patients with obesity or central obesity tended to be older (P = 0.022 for obesity; P = 0.013 for central obesity) and to have larger tumor size (P = 0.027 for obesity; P = 0.027 for central obesity). By Cox regression analysis, central obesity (DFS: HR 1.759; 95 % CI 1.009-3.065; P = 0.046. OS: HR 2.297; 95 % CI 1.184-4.456; P = 0.014) was identified as an independent prognostic factor. For central obesity with BMI = 25 kg/m2, the prognostic effect was more apparent (DFS: HR 1.845; 95 % CI 1.059-3.212; P = 0.031. OS: HR 2.377; 95 % CI 1.230-4.593; P = 0.010). Conclusion: Central obesity, especially with high BMI, was an independent prognostic factor for TNBC.