Programmed death ligand‐1 expression as immunotherapeutic target in sinonasal cancer

Background Sinonasal cancer carries a poor prognosis, especially in recurrent stages, and it is a disease with very limited treatment options. Methods The expression of programmed death ligand‐1 (PD‐L1) as a marker for immunotherapy was evaluated in 53 sinonasal squamous cell carcinoma (SCC) and 126 intestinal‐type adenocarcinoma (ITAC) samples. Results were correlated to clinicopathological characteristics and follow‐up data. Results Membranous PD‐L1 staining of tumor cells was observed in 34% (18/53) of the sinonasal SCC samples and in 17% (22/126) of the ITAC samples. The PD‐L1 positivity on infiltrating immune cells occurred in 45% (24/53) of the sinonasal SCC samples and in 33% (41/126) of the ITAC samples. Expression of PD‐L1 showed no correlation to clinicopathological parameters and was not an independent risk factor for survival. Conclusion The PD‐L1 positivity does not seem to have prognostic value. However, a proportion of patients with sinonasal SCC and ITAC may benefit from therapy with immune checkpoint inhibitors that recently have been approved for clinical application in head and neck cancer.