CADTH read with interest the commentary published on 16 December 2022, entitled “Access to Neoadjuvant Pertuzumab for HER2 Positive Breast Cancer in Canada: A Dilemma Increasingly Difficult to Explain” [1], which discusses the CADTH reimbursement review of pertuzumab for HER2-positive breast cancer. This evidence concerns the gene ERBB2 and breast carcinoma.