ESR1 and cancer: Both BC-studied groups (BMI ≥ 30 and BMI < 30) were dominantly subjected to the T0-T2 clinical tumor stage (79% and 72%, respectively), and the main pathological cancer parameters were ductal carcinoma (95%, and 94%), estrogen receptor (ER) positive (69%, and 64%), progesterone receptor (PR) positive (62%, and 57%), and histological grade G1/G2 (70%, and 67%) (Table 1).