Neoadjuvant chemotherapy enhances tumor‐specific T cell immunity in patients with HPV‐associated oropharyngeal cancer

Abstract Background Treatment of patients with newly diagnosed HPV‐associated oropharyngeal squamous cell carcinoma (OPSCC) with neoadjuvant chemotherapy (NAC) results in a high rate of 5‐year recurrence free survival with few patients requiring adjuvant treatment. We hypothesized that NAC enhances primary tumor HPV‐specific T cell responses. Methods HPV‐specific responses in tumor infiltrating lymphocytes (TILs) before and after NAC were determined using autologous co‐culture assays. Results Greater HPV16‐specific TIL responses, sometimes polyclonal, were observed after NAC compared to before in 8 of 10 patients (80%) with PCR‐verified HPV16‐positive tumors. A significant association was observed between net‐negative change in HPV‐specific TIL response and disease relapse ( p = 0.04, Mann–Whitney test), whereas pathologic complete response at time of surgery did not correlate with recurrence. Conclusions NAC induces HPV‐specific tumor T cell responses in patients with newly diagnosed HPV‐associated OPSCC; whereas lack of an increase following NAC may associate with risk of relapse.