In invasive urachal adenocarcinoma, the following four subtypes are described in the 2016 WHO classification: mucinous (colloidal) type with preponderance of extracellular mucin and malignant epithelia floating within, enteric (intestinal) type with preponderance of malignant stratified epithelium resembling colorectal adenocarcinomas, mixed type with neither a mucinous nor an enteric pattern prevailing, not other specified (NOS) type with a pattern not easily identifiable as mucinous or enteric type, and signet ring cell type with signet ring cell morphology prevailing. This evidence concerns the gene MUC5AC and bladder urachal adenocarcinoma.