Because 9–80% of urothelial carcinoma showed HER2 overexpression and about 32% exhibit gene amplification [26], different clinical trials that include anti-HER2 therapies, such as trastuzumab, pertuzumab, lapatinib, and asatinib, used as single agents or in combination with other drugs have been conducted in urothelial carcinoma [17]. The gene discussed is ERBB2; the disease is urothelial carcinoma.