The Diagnosis and Treatment of P16+ Head and Neck Squamous Cell Carcinoma Patients in Luhs Kaunas Clinics

Introduction The p16 protein is an important biomarker in the diagnosis of head and neck squamous cell carcinoma (HNSCC), often linked to HPV-driven carcinomas with better prognoses. p16+ status allows for less intensive therapeutic strategies and greater treatment responsiveness [1,2]. Aim This study was conducted to evaluate diagnostic, treatment courses as well as the outcomes of patients with p16+ HNSCC. Methods This retrospective study was conducted to evaluate the clinical course and outcome of 54 patients diagnosed with p-16 positive HNSCC at the Hospital of the Lithuanian University of Health Sciences Kaunas Clinics between 2020 and 2023. The study was approved by the Bioethics Center of LUHS (2024–BEC2–1275). Demographic data, tumor characteristics, treatment and outcomes were collected using an electronic database system. Ordinal data were presented with median and range. Differences between medians was evaluated by Mann-Whitney U test, and associations of descriptive statistics by Spearman’s chi-square test. Statistical significance was set at p<0.05. Results A total of 54 patients were included in the study with the median age of 58.0 years (range 15-79). 75.9% (n=41) were male and 24.1% (n=13) female. At the diagnosis, 50% (n=27) had early-stage disease at diagnosis (TNM stage I-II), 37% (n=20) had locally advanced disease (stage III and IVa-b), and 13% (n=7) presented with distant metastatic disease (stage IVc). A positive correlation was observed between older age and advanced-stage disease (r=0.275, p=0.045). Dysphagia (61% n=33) and cervical lymphadenopathy (50%, n=27) were most common clinical symptoms. The oropharynx was the primary tumor localization in 85% (n=46) of cases with a higher prevalence of p16+ oropharyngeal cancer in subsites outside the tonsil and base of the tongue (p<0.001). Less common sites included the hypopharynx (9%, n=5) and oral cavity (4%, n=2). Chemoradiation therapy was the predominant treatment modality (78%, n=42), with a median duration of 1.9 months (range: 1.5-25.3). Surgical treatment was performed in 35% (n=9) of early-stage disease (Stage I-II). Postoperative radiation therapy was administered to 44% (n=4) of the surgically treated patients. A complete treatment response was observed in 38 patients (median duration of 2.1 months, range: 1.0–9.8), and partial response was seen in 16 patients (median duration of 11.9, range: 1.1–27.0). The difference in treatment length between the groups was statistically significant (p<0.001). Conclusions p16+ oropharyngeal squamous cell carcinoma was the main tumor site, with chemoradiation as the main treatment approach. Complete responses were associated with shorter treatment duration, highlighting that patients with advanced HNSCC were more resistant to the treatment.