Notable exceptions included testicular non-seminoma (TCGT non-SEM; mean age 32), testicular seminoma (TCGT SEM; mean age 39), hormone receptor-positive HER2-positive invasive ductal breast carcinoma (IDC HR + HER2+; mean age 43), and low-grade serous ovarian carcinoma (LGSOC; mean age 48) (Fig. 1b). The gene discussed is ERBB2; the disease is ovarian serous carcinoma.