ABSTRACT
Introduction:
In the era of
personalized medicine and
treatment optimization, use of immune
biomarkers holds promise for estimating the
prognosis of
patients with
head and neck squamous cell carcinoma (
HNSCC) undergoing definitive
treatment.
Methods:
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.
Results:
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-L1IC 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-L1IC 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-L1IC expression along with increased TIL density in
HNSCC patients undergoing definitive
radiotherapy and
radiochemotherapy. Trial registration The study is registered with Clinicaltrials.gov. - NCT05941676.