ESR1 and ductal breast carcinoma in situ: Potentially relevant variables, as summarized in several meta-analyses and pooled analyses, include non-screen detection of DCIS (e.g., by palpation), tumor size, positive margins, grade of DCIS, comedonecrosis, architectural pattern, microcalcification, and receptor status [estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2)] [7–12].