免疫细胞高 PD-L1 表达伴 TIL（肿瘤浸润淋巴细胞）密度增加预示局部区域晚期头颈癌患者良好生存结局：一项前瞻性研究的早期结果

To evaluate the prognostic potential of immune biomarkers, we conducted a prospective monocentric cohort study with loco-regionally advanced HNSCC patients indicated for definitive radiotherapy/radiochemotherapy at the Department of Oncology, Ostrava University Hospital, Czech Republic, between June 2020 and August 2023. We focused on the expression of programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) relative to overall survival (OS) and specific survival rates. Associations between biomarkers and survival rates were assessed by crude and adjusted hazard ratios (cHR, aHR, respectively) obtained from Cox proportional hazards regression.

Among a total of 55 patients within a median follow-up of 19.7 months, there were 21 (38.2%) all-cause deaths and 15 (27.3%) cancer-related deaths. An overall survival (OS) rate of 61.8% and a disease-specific survival (DSS) rate of 72.7% were recorded. A significant association between survival rates and a 10% difference in PD-L1 expression on immune versus tumor cells (high PD-L1 IC expression) was documented regardless of the type of analysis (univariate or multivariate). In addition, a stronger association was confirmed for OS and the composite biomarker high PD-L1 IC expression along with either median-higher CD8+ TIL count or increased TIL density 30%, as indicated by an aHR of 0.08 (95% CI, 0.01 to 0.52) and 0.07 (95% CI, 0.01 to 0.46), respectively. Similar results were demonstrated for other specific survival rates. DISCUSSION: The early outcomes of the present study suggest the utility of a strong prognostic factor involving a composite biomarker high PD-L1 IC expression along with increased TIL density in HNSCC patients undergoing definitive radiotherapy and radiochemotherapy. TRIAL REGISTRATION: The study is registered with Clinicaltrials.gov. - NCT05941676.