Interactions between clinical factors, p16, and cyclin-D1 expression and survival outcomes in oropharyngeal and hypopharyngeal squamous cell carcinoma.

BACKGROUND P16 and cyclin-D1 are cell cycle proteins commonly dysregulated in head and neck carcinoma. We assessed their expression, clinicopathological variables, and overall survival (OS) in oropharyngeal and hypopharyngeal squamous cell carcinoma (SCC). METHODS Clinical characteristics and p16 and cyclin-D1 expression were evaluated in 101 patients with oropharyngeal SCC and 75 patients with hypopharyngeal SCC. Associations with OS were assessed using Cox regression and Kaplan-Meier analysis. RESULTS Compared to oropharyngeal SCC, patients with hypopharyngeal SCC were older, men, ever-smokers with higher mean Charlson Comorbidity Index (CCI), lower p16 expression, and poorer median OS (24.8 vs 62.3 months; p < .01). In oropharyngeal SCC, CCI (p < .001), cyclin-D1 (hazard ratio [HR] = 3.55; p = .007), current smoking (HR = 5.72; p = .004), and former smoking (HR = 4.12; p = .035) were independently associated with OS. In hypopharyngeal SCC, only nodal and Eastern Cooperative Oncology Group status were associated with OS. CONCLUSION In oropharyngeal SCC, cyclin-D1 expression is correlated with survival, whereas smoking status and CCI may allow further stratification of outcome.