ERBB2 and carcinoma: The most common reasons for potentially unnecessary ALND included: inflammatory carcinoma (n = 13, 29.5%), locally advanced carcinoma (n = 5, 11.4%), occult carcinoma (n = 2, 4.5%), or persistent lymphadenopathy on US examination after NAC, particularly in the tumor phenotypes HER2-positive and TNBC (n = 8, 18.2%).