Impact of Induction Chemotherapy in Locally Advanced HPV-negative Oropharyngeal Cancer. A Propensity Score-matched analysis

Aim: To estimate the clinical outcomes of induction chemotherapy (IC) followed by standard chemoradiotherapy (CRT) and CRT alone in patients with locally advanced human papilloma virus (HPV)-negative oropharyngeal squamous cell carcinoma. Patients and Methods: Consecutive patients with histologically-proven HPV-negative squamous cell carcinoma of the oropharynx were included and treated with IC-CRT or CRT alone. In order to compare treatment outcomes and toxicity between groups, patients were matched by primary tumor site and clinical disease stage. Overall survival (OS), disease free survival (DFS) and metastasis free survival (MFS) curves were calculated with the Kaplan Meier method. Results: Nine IC patients and 18 CRT patients were included. All patients completed the programmed treatment. The median follow-up was 38 months. There were no statistically significant differences in OS and DFS between groups. The 5-year MFS was 88.9% and 50.8% in the IC-CRT group, respectively. There was no meaningful difference in toxicity between patients. Conclusion: In HPV-negative patients with locally advanced oropharyngeal cancer, adding IC to standard CRT may increase the MFS rate. However no significant differences in OS and DFS were observed. More studies are needed to better elucidate the role of IC in this setting.