Survival in patients with a high prevalence of human papillomavirus-associated oropharyngeal cancer: real-world data from a national referral public hospital in South America

Background: The incidence of oropharyngeal squamous cell carcinoma (OPSCC) is rising globally. Data from South America are limited. An epidemiological shift towards a higher prevalence of human papillomavirus (HPV)-associated OPSCC has been described. This study evaluates oncological outcomes in patients with a high prevalence of HPV-associated OPSCC treated with radiotherapy at a cancer referral centre in South America. Materials and methods: A retrospective cohort study was conducted at the National Cancer Institute of Chile, including patients with non-metastatic disease treated with curative intent between 2012 and 2023. Descriptive statistics were used to summarise the data. Univariate and multivariate analyses (MVA) were conducted with logistic regression and Cox proportional hazards regression. Survival analysis was performed using the Kaplan–Meier method. Results: A total of 146 patients were analysed; 75.3% were male, with a mean age of 60.7 years. HPV positivity (p16+) was detected in 62.3%. All patients underwent radiotherapy, with 82.8% receiving concurrent chemoradiotherapy. The 5-year overall survival was 60.9% [95% confidence interval (CI): 52.7–70.3]. p16+ [hazard ratio (HR) = 0.36; 95% CI: 0.19–0.68; p < 0.01] was independently associated with improved survival, whereas a smoking history of ≥ 10 pack-years (HR = 2.18; p = 0.02) and Eastern Cooperative Oncology Group (ECOG) 2–4 (HR = 3.30; p < 0.01) were linked to worse outcomes. Conclusions: Survival outcomes in this South American population, with a high prevalence of HPV-associated OPSCC, were comparable to internationally published data. In exploratory analyses, HPV association and concurrent chemotherapy were associated with better survival outcomes, with no significant differences between cisplatin schedules.