Introduction. This review of the literature presents the results of the analysis of studies on the etiology, pathogenesis, methods of diagnosis and treatment of urothelial carcinoma in persons under 20 years of age. Worldwide, the number of such patients is small, and special programs of treatment and diagnostic measures, as well as molecular genetic panels for these patients have not yet been developed.

Materials. Relevant publications indexed in PubMed, Web of Sciences Core Collection, and Journal Citation Reports were searched. Data on risk factors and molecular-genetic changes that contribute to malignancy of the urinary epithelium, early clinical manifestations, as well as features of radiation, endoscopic, morphological diagnostics and treatment of this class of tumors are analyzed.

Results. Risk factors for urothelial carcinoma in patients younger than 20 years and older age groups are similar, however, there is a smaller role of occupational factors in young patients. Differences in the molecular subtype of tumors were found in these age groups with a predominance of urothelium-like subtype A among young patients, which leads to a more favorable prognosis of the disease and a lower rate of recurrence in individuals under 20 years of age. The main method of treatment of these neoplasms in both age groups remains transurethral resection of the bladder (TURMP), which allows radical removal of the tumor. Adjuvant treatment involving intra – bubble or systemic chemo-or immunotherapy in the postoperative period is indicated when detecting tumors with a high malignant potential, due to the risk of its metastasis and the high probability of the need for organ-carrying surgery. In clinical practice, recommendations developed for the treatment of cancer patients in the older age group are used, since there are no special guidelines for the diagnosis, treatment, and follow-up of younger patients.

Conclusions. The development of methods for the timely diagnosis, treatment and Rehabilitation of children's patients with verified bladder tumors by representatives of the medical community (oncologists, oncologists, pediatricians) remains an urgent task in the near future.