Results showed mPFS was 5.50 months (95% CI: 3.79-7.99, I2=45.3%) in HR+/HER2- mBC patients, 5.38 months (95%CI: 4.72-6.13, I2=54.8%) in mTNBC patients, and a notably longer mPFS of 9.50 months (95%CI: 8.91-10.13) in early-stage breast cancer patients. Here, ERBB2 is linked to breast cancer.