Being Overweight or Obese Increases the Risk of Progression in Triple-Negative Breast Cancer after Surgical Resection

This study aimed to evaluate the association between body mass index (BMI) and progression in triple-negative breast cancer (TNBC). We retrospectively reviewed the medical records of 50 patients with TNBC who underwent breast-conserving surgery or mastectomy between 2007 and 2014. All patients were classified according to BMI (median 23.5 kg/m(2), range 17.2–31.6 kg/m(2)): 31 patients (62%) were classified as being overweight or obese (BMI ≥ 23 kg/m(2)) and 19 patients (38%) were classified as having a normal body weight (BMI < 23 kg/m(2)). The median follow-up for patients was 31.1 months (range, 6.7–101.9 months). Progression occurred in 7 patients (14%), including 5 ipsilateral breast tumor recurrences, 2 regional lymph node metastases, and 5 distant metastases. Progression was significantly correlated with overweight or obese patients (P = 0.035), while none of the normal weight patients showed progression. The 3-year disease-free survival (DFS) and overall survival (OS) rates were 85.0% and 87.7%, respectively. DFS was significantly reduced in overweight or obese patients compared to that in normal weight patients (P = 0.035). However, OS was not significantly compromised by being overweight or obese (P = 0.134). In conclusion, being overweight or obese negatively affects DFS in TNBC patients.