ESR1 and invasive lobular breast carcinoma: After excluding invasive ductal carcinoma, histology results for the ER-positive/HER2-negative type patients were myxoid carcinoma (n = 14), invasive lobular carcinoma (n = 5), and apocrine carcinoma (n = 1), while those in the HER2-positive type were myxoid carcinoma (n = 3), invasive lobular carcinoma (n = 2), and apocrine carcinoma (n = 2), and in triple-negative type invasive lobular carcinoma (n = 1) and apocrine carcinoma (n = 3).