Histologic findings of the transurethral resected bladder tissue. (A) Endocervicosis showing round to branched endocervical-like glands with surrounding smooth muscle in the bladder (H + E × 40). (B) Surface mucinous epithelium delineated from urothelium (Southgate's mucicarmine x 40). (C) CK5/6 decorating basal cells of urothelium while surface mucinous epithelium is immunonegative (x 40). (D) Nuclear ER immunopositivity is noted in the surface mucinous epithelium and adjacent endocervicosis gland (x 40).