The Role of Body Mass Index in Triple Negative Breast Cancer

Background: Triple-negative breast cancer (TNBC) has none of the targeted treatment choices due to its distinct biological property, making this subtype a unique disease. In this study, we evaluated the impact of obesity on clinical outcomes of TNBC. Methods: The data of breast cancer patients admitted to our department were collected. TNBC was defined as lack of estrogen receptor (ER), progesterone receptor (PR) and HER-2. The body mass index (BMI) of 112 TNBC patients was calculated with weight at the time of diagnosis and height. The patients were classified into groups with a BMI of < 25 (normal/underweight), 25-29.9 (overweight) or ≥ 30 (obese). After a mean follow-up of 23.2 ± 15.5 months, there were 12 recurrences (10.71%) and 6 deaths (5.35%). Disease-free survival (DFS) and overall survival (OS) were assessed. Results: The survival analyses of all the patients did not demonstrate any differences in OS or DFS in obese as compared to non-obese patients. However, we showed that obesity was associated with a poorer OS for postmenopausal TNBC patients (p < 0.05). Conclusion: Obesity is related to a poorer OS in postmenopausal TNBC patients. Due to the heterogeneous disease profile of TNBC, larger randomized studies will be needed to clarify the exact role of obesity in TNBC.