ESR1 and triple-negative breast carcinoma: When authors investigated the diversity of the microbiome in the four major types of breast cancer (endocrine receptor (ER) positive, triple positive, HER2+ positive and triple negative breast cancers), two distinct and significantly different patterns were detected, one for the triple negative and triple positive breast cancer types, and another for the ER+ and HER2+ positive breast cancer samples, compared to healthy breast control tissue [70].