BACKGROUND: We examined PD-L1 expression on tumor cells (TCs) and immune cells (ICs) and density of CD3+ and CD8+ tumor-infiltrating lymphocytes (TILs) in patients with oropharyngeal squamous cell carcinoma (OPSCC) and investigated their significance on clinicopathological characteristics and clinical outcomes. METHODS: In a cohort of 65 patients treated by definitive intensity-modulated radiotherapy (IMRT) with curative intent, immunohistochemical analysis of PD-L1 expression on TCs and ICs, and TIL subtyping was performed on primary biopsy tumor tissues, followed by prognostic evaluation of these immune response-related parameters including classification into four tumor immune microenvironment (TIM) types. To evaluate HPV status, p16 immunohistochemistry was performed. RESULTS: Densities of CD3+ and CD8+ TILs and PD-L1 expressions on TCs and ICs were significantly higher in p16+/HPV-mediated OPSCC. Patients with high densities of stromal CD8+ TILs displayed significantly better overall survival (OS) and progression-free survival (PFS). PD-L1 expression neither on tumor cells nor on immune cells affected survival outcomes. Distribution of TIM types based on the combination of PD-L1 expression on TCs and densities of CD8+ TILs is significantly different in p16+ compared with p16- OPSCC. In type III TIM (TC-PD-L1+/low CD8+ TIL density), significantly better OS was shown in p16+ group compared with p16- OPSCC. CONCLUSION: The prognostic and predictive role of tumor immune microenvironment was confirmed for patients with OPSCC. Combining HPV status with the evaluation of densities of CD8+ TILs and PD-L1 expression including TIM classification might be of high clinical interest and warrants further prospective evaluation.

1st Department of Pathology Faculty of Medicine Masaryk University Brno Czech Republic

1st Department of Pathology St Anne's University Hospital Brno Czech Republic

Central European Institute of Technology Masaryk University Brno Czech Republic

Department of Radiation Oncology Faculty of Medicine Masaryk University Brno Czech Republic

Department of Radiation Oncology Masaryk Memorial Cancer Institute Brno Czech Republic

Research Centre for Applied Molecular Oncology Masaryk Memorial Cancer Institute Brno Czech Republic

See more in PubMed

Chaturvedi AK, Engels EA, Pfeiffer RM, et al. Human papillomavirus and rising oropharyngeal cancer incidence in the United States. J Clin Oncol. 2011;29(32):4294-4301.

Kim HS, Lee JY, Lim SH, et al. Association between PD-L1 and HPV status and the prognostic value of PD-L1 in oropharyngeal squamous cell carcinoma. Cancer Res Treat. 2016;48(2):527-536.

Ang KK, Harris J, Wheeler R, et al. Human papillomavirus and survival of patients with oropharyngeal cancer. N Engl J Med. 2010;363(1):24-35.

Fakhry C, Westra WH, Li S, et al. Improved survival of patients with human papillomavirus-positive head and neck squamous cell carcinoma in a prospective clinical trial. J Natl Cancer Inst. 2008;100(4):261-269.

Lechien JR, Seminerio I, Descamps G, et al. Impact of HPV infection on the immune system in oropharyngeal and non-oropharyngeal squamous cell carcinoma: a systematic review. Cells. 2019;8(9):1061.

Ward MJ, Thirdborough SM, Mellows T, et al. Tumour-infiltrating lymphocytes predict for outcome in HPV-positive oropharyngeal cancer. Br J Cancer. 2014;110(2):489-500.

Näsman A, Romanitan M, Nordfors C, et al. Tumor infiltrating CD8+ and Foxp3+ lymphocytes correlate to clinical outcome and human papillomavirus (HPV) status in tonsillar cancer. PLoS One. 2012;7(6):e38711.

Hong AM, Ferguson P, Dodds T, et al. Significant association of PD-L1 expression with human papillomavirus positivity and its prognostic impact in oropharyngeal cancer. Oral Oncol. 2019;92:33-39.

De Meulenaere A, Vermassen T, Aspeslagh S, et al. Turning the tide: Clinical utility of PD-L1 expression in squamous cell carcinoma of the head and neck. Oral Oncol. 2017;70:34-42.

Flies DB, Sandler BJ, Sznol M, Chen L. Blockade of the B7-H1/PD-1 pathway for cancer immunotherapy. Yale J Biol Med. 2011;84(4):409-421.

Pruneri G, Gray KP, Vingiani A, et al. Tumor-infiltrating lymphocytes (TILs) are a powerful prognostic marker in patients with triple-negative breast cancer enrolled in the IBCSG phase III randomized clinical trial 22-00. Breast Cancer Res Treat. 2016;158(2):323-331.

Balermpas P, Rödel F, Rödel C, et al. CD8+ tumour-infiltrating lymphocytes in relation to HPV status and clinical outcome in patients with head and neck cancer after postoperative chemoradiotherapy: A multicentre study of the German cancer consortium radiation oncology group (DKTK-ROG). Int J Cancer. 2016;138(1):171-181.

Jung AC, Guihard S, Krugell S, et al. CD8-alpha T-cell infiltration in human papillomavirus-related oropharyngeal carcinoma correlates with improved patient prognosis. Int J Cancer. 2013;132(2):E26-36.

Nordfors C, Grün N, Tertipis N, et al. CD8+ and CD4+ tumour infiltrating lymphocytes in relation to human papillomavirus status and clinical outcome in tonsillar and base of tongue squamous cell carcinoma. Eur J Cancer. 2013;49(11):2522-2530.

Oguejiofor K, Galletta-Williams H, Dovedi SJ, et al. Distinct patterns of infiltrating CD8+ T cells in HPV+ and CD68 macrophages in HPV- oropharyngeal squamous cell carcinomas are associated with better clinical outcome but PD-L1 expression is not prognostic. Oncotarget. 2017;8(9):14416-14427.

Lee YS, Park JY, Cho KJ, et al. Composition of inflammatory cells regulating the response to concurrent chemoradiation therapy for HPV (+) tonsil cancer. Oral Oncol. 2015;51(2):1113-1119.

Amin MB, Edge S, Greene F, et al., eds. AJCC Cancer Staging Manual (8th edn New York: Springer International Publishing; 2017.

De Meulenaere A, Vermassen T, Aspeslagh S, et al. Tumor PD-L1 status and CD8(+) tumor-infiltrating T cells: markers of improved prognosis in oropharyngeal cancer. Oncotarget. 2017;8(46):80443-80452.

Kwon MJ, Rho YS, Nam ES, et al. Clinical implication of programmed cell death-1 ligand-1 expression in tonsillar squamous cell carcinoma in association with intratumoral heterogeneity, human papillomavirus, and epithelial-to-mesenchymal transition. Hum Pathol. 2018;80:28-39.

Ukpo OC, Thorstad WL, Lewis Jr JS. B7-H1 expression model for immune evasion in human papillomavirus-related oropharyngeal squamous cell carcinoma. Head Neck Pathol. 2013;7(2):113-121.

Lyford-Pike S, Peng S, Young GD, et al. Evidence for a role of the PD-1:PD-L1 pathway in immune resistance of HPV-associated head and neck squamous cell carcinoma. Cancer Res. 2013;73(6):1733-1741.

Sato F, Ono T, Kawahara A, et al. Prognostic impact of p16 and PD-L1 expression in patients with oropharyngeal squamous cell carcinoma receiving a definitive treatment. J Clin Pathol. 2019;72(8):542-549.

Wang HF, Wang SS, Tang YJ, et al. The double-edged sword-how human papillomaviruses interact with immunity in head and neck cancer. Front Immunol. 2019;10:653.

Subbarayan RS, Arnold L, Gomez JP, Thomas SM. The role of the innate and adaptive immune response in HPV-associated oropharyngeal squamous cell carcinoma. Laryngoscope Investig Otolaryngol. 2019;4(5):508-512.

Ruangritchankul K, Sandison A, Warburton F, et al. Clinical evaluation of tumour-infiltrating lymphocytes as a prognostic factor in patients with human papillomavirus-associated oropharyngeal squamous cell carcinoma. Histopathology. 2019;75(1):146-150.

Partlová S, Bouček J, Kloudová K, et al. Distinct patterns of intratumoral immune cell infiltrates in patients with HPV-associated compared to non-virally induced head and neck squamous cell carcinoma. Oncoimmunology. 2015;4(1):e965570.

Solomon B, Young RJ, Bressel M, et al. Prognostic significance of PD-L1(+) and CD8(+) immune cells in HPV(+) oropharyngeal squamous cell carcinoma. Cancer Immunol Res. 2018;6(3):295-304.

Lindquist D, Romanitan M, Hammarstedt L, et al. Human papillomavirus is a favourable prognostic factor in tonsillar cancer and its oncogenic role is supported by the expression of E6 and E7. Mol Oncol. 2007;1(3):350-355.

Rasmussen JH, Lelkaitis G, Håkansson K, et al. Intratumor heterogeneity of PD-L1 expression in head and neck squamous cell carcinoma. Br J Cancer. 2019;120(10):1003-1006.

Badoual C, Hans S, Merillon N, et al. PD-1-expressing tumor-infiltrating T cells are a favorable prognostic biomarker in HPV-associated head and neck cancer. Cancer Res. 2013;73(1):128-138.

Fukushima Y, Someya M, Nakata K, et al. Influence of PD-L1 expression in immune cells on the response to radiation therapy in patients with oropharyngeal squamous cell carcinoma. Radiother Oncol. 2018;129(2):409-414.