Atypical hyperplasia appeared more strongly associated with both HER2+ subtypes than ER/PR+HER2− breast cancer (ER/PR+HER2+ HR = 2.56, 95% CI 1.25–4.85; ER/PR−HER2+ HR = 3.01, 95% CI 0.83–1.99). Here, ERBB2 is linked to breast carcinoma.