The impact of HPV infection, smoking history, age and operability of the patient on disease-specific survival in a geographically defined cohort of patients with oropharyngeal squamous cell carcinoma

Conclusions: Patients with human papillomavirus (HPV)-positive tumours had better 5-year disease-specific survival (DSS) than HPV-negative patients. TNM score only predicted prognosis among HPV-negative patients. A previous history of smoking and age at diagnosis predicted DSS among HPV-positive patients whereas operability at diagnosis predicted DSS among both HPV-positive and HPV-negative patients. Objectives: HPV is a risk factor for oropharyngeal squamous cell carcinoma (OPSCC). The extent to which smoking, age and operability could play a role in HPV-positive surgically treated head and neck SCCs has not been extensively addressed previously and this study aimed to evaluate these factors. Methods: We identified 232 patients with OPSCC, of which 186 from the tonsil or base of the tongue region were treated in the period 1992-2008 in Western Norway. The 5-year DSS was recorded. Details on smoking history and whether the lesion was operable or not, as well as clinical information, were obtained retrospectively from the hospital records. Results: TNM stage predicted survival only among HPV-negative patients. A previous smoking affected prognosis only among HPV-positive patients (relative risk (RR) = 2.5; confidence interval (CI) = 1.0-6.2; p = 0.05). Increasing age of the patient had a negative effect on survival in HPV-positive patients only, especially among the oldest quartile (RR = 4.4; CI = 2.0-9.0; p < 0.001). Whether the tumour was operable or not uniquely predicted DSS both among HPV-positive (RR = 0.34; CI = 0.13-0.93; p < 0.05) and HPV-negative (RR = 0.25; CI = 0.10-0.66; p < 0.01) patients with tonsil/base of the tongue SCC.