PIK3CA and breast cancer: Pooled ORR demonstrated that PI3K inhibitors generated 1.98 [95% CI, 1.46 to 2.70] odds ratio (OR) in HR+/PIK3CA-mutated breast cancer patients and 1.09 [95% CI, 0.78 to 1.53] odds ratio (OR) in HR+/PIK3CA wild-type breast cancer patients.