Association Between PD-L1 and HPV Status and the Prognostic Value of PD-L1 in Oropharyngeal Squamous Cell Carcinoma.
- Author:
Hae Su KIM
1
;
Ji Yun LEE
;
Sung Hee LIM
;
Keunchil PARK
;
Jong Mu SUN
;
Young Hyeh KO
;
Chung Hwan BAEK
;
Young Ik SON
;
Han Sin JEONG
;
Yong Chan AHN
;
Min Young LEE
;
Mineui HONG
;
Myung Ju AHN
Author Information
- Publication Type:Original Article
- Keywords: Programmed death ligand-1 (PD-L1); Human papillomavirus (HPV); Oropharyngeal Neoplasms; Immune checkpoint inhibitor; Immune therapy
- MeSH: Carcinoma, Squamous Cell*; Follow-Up Studies; Humans; Immunohistochemistry; Membranes; Multivariate Analysis; Oropharyngeal Neoplasms; Prevalence; Prospective Studies; Smoke; Smoking; United Nations
- From:Cancer Research and Treatment 2016;48(2):527-536
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: Oropharyngeal squamous cell carcinoma (OSCC) has been recognized as an immunosuppressive disease. Various mechanisms have been proposed for immune escape, including dysregulation of immune checkpoints such as the PD-1:PD-L1 pathway. We investigated the expression of programmed cell death-ligand 1 (PD-L1) in HPV-negative and HPV-positive OSCC to determine its prevalence and prognostic relevance. MATERIALS AND METHODS: Using immunohistochemistry, 133 cases of OSCC were evaluated for expression of PD-L1. Formalin-fixed paraffin-embedded tumor samples were stained with monoclonal antibody (clone 5H1) to PD-L1. PD-L1 positivity was defined as membrane staining in ≥20% of tumor cells. Correlations between PD-L1 expression and HPV status and survival parameters were analyzed. RESULTS: Of the 133 patients, 68% showed PD-L1 expression, and 67% of patients were positive for p16 expression by immunohistochemistry. No significant difference in PD-L1 expression was observed between HPV(-) and HPV(+) tumors (61% vs. 71%, p=0.274). No significant difference in age, gender, smoking history, location of tumor origin, or stage was observed according to PD-L1 status. With a median follow-up period of 44 months, older age (≥65) (p=0.017) and T3-4 stage (p<0.001) were associated with poor overall survival (OS), whereas PD-L1 expression did not affect OS in univariate and multivariate analysis. CONCLUSION: PD-L1 expression was observed in the majority of OSCC patients regardless of HPV status. Further large prospective studies are required to determine the role of PD-L1 expression as a prognostic or predictive biomarker, and clinical studies of immune checkpoint inhibitors in OCSS are warranted regardless of HPV status.
