Stage 0 includes: 0a (Ta, N0, M0); 0is (Tis, N0, M0). Ta: Noninvasive papillary carcinoma. Tis: Carcinoma in situ: "flat tumor". N0: No regional lymph node metastasis. M0: No distant metastasis. (AJCC 6th and 7th eds.). The disease is non-invasive bladder urothelial carcinoma (MONDO_0003930, a Monarch Disease Ontology term). Also known as: stage 0 bladder urothelial cancer, stage 0 bladder urothelial carcinoma, stage 0 bladder urothelial carcinoma aJCC v6, stage 0 bladder urothelial carcinoma aJCC v6 and v7, stage 0 bladder urothelial carcinoma aJCC v7, stage 0 transitional cell carcinoma of bladder, stage 0 transitional cell carcinoma of the bladder, stage 0 transitional cell carcinoma of the urinary bladder.