ESR1 and breast neoplasm: Using an atlas of 204,728 peaks across all ILC and IDC breast tumors (n = 67) [21], we grouped tumors according to their histological subtypes and hormone receptor status according to their clinical annotation [23] [24]: ER+ /HER2- ILCs (n = 13), ER+ /HER2- IDCs (n = 30), and ER+ /HER2+ IDCs (n = 7).