ERBB2 and parotid gland acinic cell carcinoma: Of the 20 patients enrolled, 13 patients had HER2-negative breast cancer (n = 11 hormone receptor positive and n = 2 triple-negative breast cancer) and 7 patients had other tumor types (n = 3 pancreatic cancer and n = 1 each of colon cancer, mixed Mullerian uterine cancer, testicular cancer and parotid acinic cell carcinoma) as shown in Table 1.