Background: In Brazil, almost 75% of individuals rely on the public healthcare system. However, disparities between the public system (PHS) and private health insurance (HIS) remain evident in oncology care.
Objectives: This study aims to evaluate the impact of referral source on the diagnosis, time from diagnosis to treatment and post-treatment outcomes among patients with oral cavity (OCC) and oropharyngeal (OPC) cancer in Brazil.
Methods: Cross-sectional study based on secondary data collected from Hospital-based Cancer Registries in Brazil. Sociodemographic and clinical characteristics, and time from diagnosis to treatment, were analyzed. Logistic regression was used to calculate odds ratios for each stage of cancer care. The median time from diagnosis to treatment was calculated according referral source by each Brazilian federative state.
Results: From 2010-2022, 62,178 cases of OCC (n=33,485) and OPC (n=28,693) were registered in Brazilian system. About ethnicity, 50% (n=19,295) were brown and  42.5% (n=16,552) were white. About 60% (n=29,861) of patients were diagnosed with stage IV and 55.4% (n=30,620) received treatment over 60 days after diagnosis. Of 41,248 patients, 36,242 (87.9%) were referred through the PHS and 5,007 (12.1%) through the HIS. Males (79.3%, n=28,736), individuals under 50 years old (18.4%, n=6,678) and non-black individuals (54.8%, n=19,918) have higher frequency of PHS referrals but were diagnosed at clinical-stage IV in 60.7% (n=15,543), while early clinical-stage in 18.1% (n=4,630), HIS were 57.4% (n=2,024) and 20.9% (n=737), respectively. The diagnosis-to-treatment interval was longer for patients referred via PHS 56.1% (n=17,955). Patients with clinical-stage IV were associated with a 22% higher likelihood of being referred via PHS. Regarding treatment stage, patients who waited more than 60 days for treatment had a 34% higher [CI 1.16 - 1.50] likelihood of being referred via PHS. The associated outcomes from patients referred via PHS were progressive/relapsed disease (OR 1.28 [CI 1.08–1.52]) and death post-treatment [OR 1.36 CI 1.15–1.61]. The time-to-treatment initiation for OCC and OPC in Brazil was shorter in HIS than PHS for both clinical-stages (early/advanced).
Conclusions: Referral through the PHS is associated with advanced clinical staging, delays in treatment initiation and worst post-treatment outcomes in patients with OCC and OPC, highlighting persistent inequalities in access to timely and appropriate cancer care in Brazil.