ESR1 and carcinoma: GRCC were statistically more likely to be Grade III (GRCC: 41.3% vs. non-GRCC carcinomas: 29.2%) and grade IV (GRCC: 3.2% vs. non-GRCC carcinomas: 1.4%), ER negative (GRCC: 40.3% vs. non-GRCC carcinomas: 17.9%), PR negative (GRCC: 58.3% vs. non-GRCC carcinomas: 27.4%), triple negative (GRCC: 44.8% vs. non-GRCC carcinomas: 10.4%), T2 status (GRCC: 36.8% vs. non-GRCC carcinomas: 23.6%), and positive for brain metastasis at diagnosis (GRCC: 3.4% vs. non-GRCC carcinomas: 0.4%).