High-quality studies (NOS score > 6) were used to perform the sensitivity analysis, and the results were consistent (HER2-enriched molecular subtype of breast cancer: OR = 1.133, 95% CI [1.057–1.215], p < 0.001; TNBC molecular subtype: OR = 1.237, 95% CI [1.094–1.399], p = 0.001). This evidence concerns the gene ERBB2 and breast cancer.