ESR1 and neoplasm: There were significant differences in MetaSite Score tertile distribution (high, intermediate, low MetaSite Score) for age 40 or younger (37% vs. 31% vs. 21%, p = 0.02) and older than 60 years (34% vs. 31% vs. 49%, p = 0.04), ER (48%, vs. 70% vs 67%, p < 0.001) and PR (49% vs. 65% vs. 68%, p < 0.001) expression, and any grade (6% vs. 18% vs. 62% for low grade, p < 0.001; 20% vs. 40% vs. 44% for intermediate grade, p < 0.001; 73% vs. 42% vs. 28% for high grade, p < 0.001), but not tumor size or axillary nodal metastases.