ERBB2 and breast cancer: To determine the utility and identify patients who could benefit from HER2-targeted therapy in low- and high-grade NMIBC, we analysed HER2 protein overexpression by IHC and gene amplification by fluorescent in situ hybridization (FISH) according to the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2013 Guidelines for breast cancer.