Prognostic Value of Combined Programmed Cell Death 1 Ligand and p16 Expression Predicting Responsiveness to Radiotherapy in Patients with Oropharyngeal Squamous Cell Carcinoma
10.3342/kjorl-hns.2019.00619
- Author:
Minsu KWON
1
;
Dae Hwan KIM
;
Ki Ju CHO
;
Youngchul KIM
;
Jin Pyeong KIM
;
Bae Kwon JEONG
;
Jong Sil LEE
;
Ji Hyun SEO
;
Jung Je PARK
Author Information
1. Department of Otorhinolaryngology, Eulji Medical Center, Eulji University School of Medicine, Seoul, Korea.
- Publication Type:Original Article
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
2019;62(12):712-719
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND AND OBJECTIVES:This study examined the expressions of p16 and the programmed cell death 1 ligand (PD-L1) in patients with oropharyngeal cancer (OPC) treated with radiotherapy (RT) to identify the correlation between p16 and PD-L1 expression, and to examine the prognostic significance of these markers for OPC patients receiving RT.SUBJECTS AND METHOD: Forty-eight OPC patients diagnosed and treated at a tertiary referral hospital were enrolled in this retrospective analysis. Patients were initially treated with RT or chemoradiotherapy (CRT) with curative intent and completed the planned schedule. Expression of p16 and PD-L1 by primary tumors was evaluated by immunohistochemistry, and results were interpreted separately and dichotomized according to outcome analyses.
RESULTS:Of the 48 patients, 25 (52.1%) expressed p16 and 15 (31.3%) expressed PD-L1. Expression of these markers showed a mutual positive correlation (p=0.046). Positive PD-L1 expression was associated with poor complete remission (CR) rates after RT (p=0.040). Positive p16 expression was associated with better recurrence-free survival (RFS) (p=0.004) but not overall survival (OS) (p=0.192). PD-L1 expression showed no independent association with survival (p>0.05); however, PD-L1 expression tended toward poorer RFS, even in p16-positive individuals.
CONCLUSION:There was a positive correlation between the expression of p16 and PD-L1 in OPCs. PD-L1 expression was associated with poorer CR rates after RT or CRT. PD-L1 alone did not show an association with RFS or OS, but when combined with p16, it tended toward poorer RFS, even in p16-positive cases.
