Evaluation of immunohistochemical expression of p53, p21, p27, cyclin D1, and Ki67 in oral and oropharyngeal squamous cell carcinoma.

ABSTRACT

BACKGROUND: The purpose of this study was to evaluate whether the immunohistochemical expression of p53, p21, p27, cyclin D1, and Ki67 can predict therapy response and survival in patients with oral and oropharyngeal squamous cell carcinoma treated with preoperative chemoradiation. METHODS: Biomarker expression was evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded pretreatment biopsies of 111 homogenously treated patients. We assessed the association between clinicopathological variables including response to neoadjuvant chemoradiotherapy as well as the survival of the patients and the expression of the biomarkers as both dichotomized (positive vs. negative) and continuous variables. RESULTS: Biomarker overexpression on the basis of pre-selected cutoff points was seen in 66 of 111 (59%) cases for p53, in 77 (69%) for p21, in 48 (43%) for p27, in 81 (73%) for cyclin D1, and in 54 (49%) cases for Ki67, respectively. None of the examined biomarkers was able to predict response to neoadjuvant chemoradiotherapy or was associated with survival outcome. Post-treatment pathologic TNM stage (P < 0.001), pathologic response (P < 0.001), and perineural invasion (P < 0.001) were the only factors having a significant effect on recurrence-free survival. Post-treatment pathologic N stage (P = 0.005), post-treatment pathologic TNM stage (P < 0.001), pathologic response (P < 0.001), and perineural invasion (P = 0.001) had a significant impact on overall survival. CONCLUSIONS: Our results suggest that the biomarkers p53, p21, p27, cyclin D1, and Ki67 have no impact on treatment response and survival in patients with oral and oropharyngeal cancer treated with preoperative chemoradiation.