Other Than Complete Response in Oropharyngeal Carcinoma: Patient and Tumor-Related Factors

Oropharyngeal carcinoma represents a tumor with an increased concern in human health and treatment strategy. This study aims to identify any tumor or patient-related characteristics capable of predicting response to non-surgical curative treatment in a cohort of oropharyngeal squamous cell carcinoma and define oncological outcomes of overall survival and progression-free survival.

A monocentric retrospective cohort study was performed, including 223 patients with non-metastatic oropharyngeal squamous cell carcinoma treated with curative intent with a non-surgical strategy. Patients were treated at the University Hospital of Modena (Italy) after a multidisciplinary evaluation between January 2010 and December 2021. The treatment response was assessed by using the RECIST 1.1 Criteria on imaging performed 3 months after treatment.

Tonsil subsite and stage I were independently associated with a complete treatment response (OR = 0.53, p = 0.05, and OR = 0.32, p = 0.01, respectively). The association between smoking and p16- status resulted in a higher probability of a not-complete response (OR = 1.72, p = 0.05). Similar results were found for soft palate subsite, cT4, N2 in the p16+ group, and stage IVb in the p16- group. Conversely, cT1 was associated with a higher probability of complete response. Age and the extension to nearby structures did not influence the response.

This retrospective study shows a possible stratification of patients with oropharyngeal squamous cell carcinoma based on factors that influence treatment response rate. The identification of a phenotype of a non-responding tumor could better define therapeutic and follow-up programs.

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