ESR1 and neoplasm: In addition to the antigens described here, the original tumor was positive for CKC, CK7 and CK 5/6, negative for GATA3, CDX2, ERα, CK20,p63, AFP, CA19.9, TTF1 and PAX 8 and with patchy/focal staining for calretinin, CD10, RCC, BerEP4 and WT‐1 (data not shown).