Potential association of the prognostic index and survival in patients with p16-positive oropharyngeal squamous cell carcinoma.

Background: The aim was to assess the prognostic value of the newly proposed prognostic index (PI) in patients with p16-positive oropharyngeal squamous cell carcinoma.

Methods: Patients treated with primary surgery from 2012 to 2019 with available preoperative (0-2 days) values of C‑reactive protein and white blood cell counts needed for calculation of the PI, were included. Main outcome measures were overall survival (OS) and disease-free survival (DFS). The PI was dichotomized into low (PI = 0) and high (PI ≥ 1).

Results: In this study 36 patients were included. Average overall (OS) and disease-free survival (DFS) were 3.3 years (range 0.2-12.3 years) and 2.8 years (0.0-9.8 years), respectively. The overall mortality was 16.7% (n = 6) and a recurrent disease was observed in 30.6% of patients (n = 11). Low PI was associated with better overall survival (mean OS 10.1 ± 1.4 years, 95% confidence interval, CI 7.3-12.9 years vs. 1.9 ± 0.4, 95% CI 1.3-2.6 years, p < 0.01; mean DFS 8.5 ± 0.7 years, 95% CI 7.1-9.6 years vs. 1.0 ± 0.3 years, 95% CI 0.5-1.5 years, p < 0.01).

Conclusion: The PI might be an easily obtainable outcome prognosticator in p16-positive oropharyngeal squamous cell carcinoma patients. Analyzing routinely obtained blood samples can contribute to identifying high-risk patients.