The intricate relationship between obesity, type 2 diabetes and female breast cancer: A retrospective study of 335 women

Background: Type 2 diabetes (T2D) is a risk factor for female breast cancer (FBC). Obesity has also been associated with FBC, also depending on menopausal status. This study aimed to evaluate the impact of obesity and T2D on the development, aggressiveness, and invasiveness of FBC. Methods: Demographic, clinical, and histopathological data from 335 women with FBC were collected, and analyzed according to weight category (102 normal weight, 117 overweight, and 116 living with obesity) and the presence/absence of T2D. Results: Age at oncologic diagnosis was not statistically significantly different for body weight; women with overweight or obesity were more likely to have an oncologic diagnosis after menopause than normal weight (p < 0.001). The presence of overweight/obesity and T2D seemed to be associated with a higher incidence of metastasis, recurrence, and triple-negative breast cancer (TNBC) subtype (p < 0.001). Excess body weight was also associated with high histologic grade (G3) (p < 0.005). Conclusions: These results confirm excess body weight and T2D as unfavorable prognostic factors in terms of the presence of the TNBC subtype, tumor metastasis, recurrence, and aggressiveness (G3 and Ki-67 > 20%). This study highlights the importance of prevention in all women, with early screening, and adequate nutritional programs.