p16 status or response to induction chemotherapy, which predicts survival outcomes in Chinese oropharyngeal cancer treated with definitive radiotherapy?

Ruichen Li; Yang Zhao; Kangting Wu; Huiqing Li; Xinru Lin; Liting Zhu; Yi Zhu; Xiaoshen Wang

doi:10.1016/j.radonc.2024.110578

p16 status or response to induction chemotherapy, which predicts survival outcomes in Chinese oropharyngeal cancer treated with definitive radiotherapy?

Radiother Oncol. 2024 Oct 10:110578. doi: 10.1016/j.radonc.2024.110578. Online ahead of print.

Authors

Ruichen Li¹, Yang Zhao¹, Kangting Wu¹, Huiqing Li¹, Xinru Lin¹, Liting Zhu¹, Yi Zhu², Xiaoshen Wang³

Affiliations

¹ Department of Radiation Oncology, Eye & ENT Hospital of Fudan University, Shanghai 200031, China.
² Department of Radiation Oncology, Eye & ENT Hospital of Fudan University, Shanghai 200031, China. Electronic address: zhuyi1113@hotmail.com.
³ Department of Radiation Oncology, Eye & ENT Hospital of Fudan University, Shanghai 200031, China. Electronic address: xiaoshen.wang@fdeent.org.

PMID: 39395672
DOI: 10.1016/j.radonc.2024.110578

Abstract

Purpose: To identify whether p16 status or response to induction chemotherapy (IC) predicts the radiotherapy (RT) response and survival outcomes in Chinese oropharyngeal squamous cell carcinoma (OPSCC).

Methods: A total of 211 patients, including 128 p16-positive and 83 p16-negative were analyzed. All patients underwent IC followed by definitive RT or concurrent chemoradiotherapy (CCRT). Propensity score matching (PSM) was used to eliminate the baseline variations.

Results: Age, sex, smoking history, alcohol history, and primary site were unbalanced between different p16 status subgroups. Before PSM, the objective response rates to IC between p16-positive and p16-negative groups were 80.5 % and 85.5 % (p = 0.344). After RT, the complete response (CR) rates were 73.4 % and 66.3 %, respectively (p = 0.264). IC-sensitive (IC-s) subgroups had a higher percentage of RT-CR rate than the IC-resistant (IC-r) subgroups in both p16-positive and p16-negative patients. IC-s showed significant improvement in cancer-specific survival (CSS) (92.9 % vs. 53.6 %, p < 0.0001), progression-free survival (PFS) (p < 0.0001), locoregional relapse-free survival (LRFS) (p < 0.0001) and distant metastasis-free survival (DMFS) (p = 0.025). After PSM, the CR rates among different p16 groups remained comparable following RT (71.2 % vs. 65.8 %, p = 0.476). Before or after PSM, CSS, PFS, LRFS, and DMFS were similar between different p16 status either in IC-s or IC-r subgroups (p > 0.05). IC-r was independently associated with shorter PFS (HR = 2.661, p = 0.002) and LRFS (HR = 2.876, p = 0.002; HR = 2.78, p = 0.018).

Conclusions: Response to IC is an important predictor of prognosis in Chinese OPSCC treated with definitive RT. Poor response to IC is associated with unsatisfactory outcomes either in p16-positive or p16-negative OPSCC.

Keywords: Human papillomavirus; Induction chemotherapy; Oropharyngeal squamous cell carcinoma; Radiotherapy; Survival predictive values; Treatment response.