The Nordic countries (Sweden, Denmark, Norway, Finland and Iceland) share several similarities about common history and are much alike regarding demographics, approach to the health care system, recommendations and guidelines for treatment etc. Moreover, the Nordic countries have a long tradition of collaboration and mutual exchange of ideas in both the political and the health care system.

In Urology, the Nordic countries have collaborated since the 1960’s through Scandinavian Association of Urology (Nordisk Urologisk Forening) under which disease specific collaboration groups have a long history of common studies. Regarding bladder cancer, the Nordic Urothelial Cancer Group, NUCG, has performed several randomized controlled trials (RCT’s) during the last decades. This association is founded in the national urological societies, whereas the Nordic medical oncologists have performed studies in another collaboration group, Nordic Urothelial Cancer Oncology Group, NUCOG. During the past years, NUCG and NUCOG have conducted joined meetings to exchange ideas and experience.

Focus of the NUCG over the last years has been mapping of treatment strategies of all aspects of bladder cancer in the Nordic countries to harmonize these and aim at a common Nordic approach. This work has shown that the current guidelines of the different countries and normal clinical approaches are very much alike which makes it plausible to consider the Nordic countries as one large catchment area for large scale clinical trials. Moreover, these findings have led to initiation of prospective validations studies on biomarkers and further detailed database-based studies based on national data form all countries.

The Nordic countries all have very structured national databases through the public health care system where almost 100% of all patients nationwide are registered with complete follow-up regarding recurrence, progression, and survival. Another common feature of bladder cancer treatment of all Nordic countries is that, all patients are treated at a limited number of dedicated hospitals with a high number of patients. These institutions treat all bladder cancer patients whereas none is treated at private clinics etc. Patient cohorts from these institutions therefore cover the whole spectrum of the disease without risk of selected high risk or even income patients or similar selection bias.

The incidence of bladder cancer in the Nordic countries is approximately 8,000 new patients annually with a prevalence of almost 70,000 (2015 numbers from NordCan). In a validation study in cystectomy patients from all Nordic countries, the inclusion rate is expected to be almost 1,000 new cystectomy patients per year.

The Nordic countries are therefore an obvious choice of focus for initiating large scale epidemiological studies and clinical trials on bladder cancer because of the existing structure of Nordic health care systems, comprehensive and complete data, and uniform guidelines.

Based on this, a new collaboration under the name ‘Nordic Urothelial Cancer Research Group’ (NORTH-REG) was founded in 2019 supported by Nordic Trial Alliance (NTA). NORTH-REG has a focus limited to research and works independently and not as a competitor to NUCG. NORTH-REG will be a liaison between research units across the Nordic countries with focus on organizing a multidisciplinary collaboration and support infrastructure etc. of clinical trials.