KRT20 and bladder urachal adenocarcinoma: In our analysis of a total of 116 urachal adenocarcinomas, only 4 cases were negative for CK20—an overall positive rate of 97% [1, 17, 23, 26, 27, 31, 36, 48, 56, 60, 62, 67, 74, 77, 86, 95, 99, 124–126, 128, 148, 156, 163, 164, 216, 217, 220, 240, 245, 251, 327].