Impact of referral source on diagnosis and treatment of oral cavity and oropharyngeal cancer in Brazil: a nationwide hospital cancer registry-based study.

INTRODUCTION: In Brazil, nearly 75% of the population depends on the public health system (PHS), yet disparities with private health insurance (HIS) persist in oncology care. This study aims to evaluate the impact of referral source on the diagnosis, time to treatment and post-treatment outcomes among Brazilian patients with oral cavity (OCC) and oropharyngeal (OPC) cancer. METHODS: Data from Integrador Brazilian National Cancer Institute (Instituto Nacional de Câncer, INCA) (2010-2022) were analysed. Sociodemographic and clinical variables, time from diagnosis to treatment and outcomes were assessed. Logistic regression estimated ORs for cancer care stages. Median diagnosis to treatment intervals were calculated by referral source and Brazilian state. RESULTS: A total of 62 178 cases were registered, including 33 485 OCC and 28 693 OPC. Referral information was available for 41 249 patients, of whom 87.9% were referred via PHS and 12.1% via HIS. PHS referrals were more frequent among males (79.3%), individuals <50 years (18.4%) and non-White patients (54.8%). Advanced stage (clinical stage, CS IV) was observed in 60.7% of PHS referrals versus 57.4% of HIS. Patients with CS IV had a 22% higher chance of being referred through the PHS. Those who waited more than 60 days for treatment had a 32% higher chance of being referred via PHS. The associated outcomes from PHS referred patients were progressive/relapsed disease (OR 1.28 (95% CI 1.08 to 1.52)) and death post-treatment (OR 1.36 (95% CI 1.15 to 1.61)). CONCLUSIONS: Referral through the PHS is associated with advanced clinical staging, delays in oral cancer treatment initiation and worst outcomes in OCC and OPC, underscoring persistent inequities in Brazilian cancer care.