[Network analysis of the regulation of gastrointestinal cancer treatment].

High complexity is a fundamental component of Brazil's National Policy for Cancer Prevention and Control under the Unified National Health System (SUS). The policy mandates guaranteeing comprehensive patient care. Regulation is part of the organizational structure and is responsible for defining treatment flows. In Rio de Janeiro, the Central Regulating Office launched its activities in June 2015, organizing high-complexity outpatient procedures. The current study aims to analyze commuting for treatment by individuals with gastrointestinal tumors in the state of Rio de Janeiro, before and after the implementation of regulation, from the perspective of Social Network Analysis. This ecological study compared the periods before (2013) and after (2016) implementation of the Central Regulating Office. The study drew on secondary data from the Brazilian Health Informatics Department. Two sociograms were designed for the years 2013 and 2016, correlating place of residence with place of hospitalization. This approach allowed identifying some changes in the dynamics of relations between the state's microregions after implementation of the regulation. The microregions with high-complexity oncology establishments displayed an increase in the number of hospitalizations in 2016. The microregion of Rio de Janeiro also maintained degree centrality in the two moments. The use of Social Network Analysis to assess public policies can contribute to health planning and management.