PD-L1 is a positive prognostic factor in squamous cell carcinoma of the nasal vestibule.

Background: Aim was to analyse the role of PD-L1 in squamous cell carcinomas of the nasal vestibule. Advanced squamous cell carcinoma of the nasal vestibule is a highly aggressive tumour. The role of PD-L1 expression is unclear in this tumour type.
Methodology: Forty-six patients diagnosed between 1995 and 2014 were analyzed. Baseline characteristics and outcome were correlated to immunohistochemical staining of PD-L1. PD-L1 positivity of tumour cells and tumour infiltrating immune cells (TIIC) was defined by any staining of more than 1% of the tumour cells.
Results: PD-L1 expression was interpretable in 31 of 46 patients (67.4%). PD-L1 positivity was present in 14 (45.2%) patients tumour cells and 17 (54.8%) patients TIIC. PD-L1 positivity of tumour cells was associated with a favourable disease free survival (p=0.019).
Conclusions: Positivity for PD-L1 in tumour cells is a prognostic factor in squamous cell carcinoma of the nasal vestibule and might enable a patient-tailored treatment.