Timing and frequency of oropharyngeal squamous cell carcinoma recurrences after treatment with curative intent

Background: The increasing number of patients under surveillance after treatment of human papillomavirus-related oropharyngeal squamous cell carcinoma (OPSCC) places a great burden on healthcare providers. Aims/objectives: The aim of this study was to explore OPSCC recurrences in a long follow-up period: their site, frequency and timepoint after primary treatment, treatment and outcome. The secondary aim was to investigate if the recurrences are diagnosed on routine follow-up visits, and if the p16 status will have an effect on the pattern of recurrences. Material and methods: We analyzed recurrences within a 10-year follow-up period after completed curatively intended treatment among OPSCC patients in Finland treated between 2000 and 2009. Patient-, tumor-, treatment- and follow-up -related parameters were investigated. Results: Out of 495 patients with no residual tumor during the first six months, 71 (14%) were diagnosed with a recurrence, of which 47 were locoregional and 28 were treated with curative intent. Of the recurrences, 86% were diagnosed during the first 36 months after primary treatment. Only ten recurrences appeared after 36 months. The median OS after recurrence was 10.9 months. Conclusions and significance: Routine follow-up longer than three years after treatment seems not to be effective in terms of detecting OPSCC recurrences.