Correlation between proliferating cell nuclear antigen and p53 protein expression and 5-year survival rate in nasopharyngeal carcinoma

PURPOSE: To assess the prognostic significance of p53 protein and proliferating cell nuclear antigen (PCNA) expression in nasopharyngeal carcinoma. MATERIALS AND METHODS: This study included 79 patients who had received treatment and regular follow-up for at least 5 years at a single institute. We used immunohistochemistry staining to assess p53 protein expression and PCNA labeling index (LI). Analyses were conducted on the association between each of the 2 biomarkers and pathological subtypes, TNM stage, the presence of locoregional recurrence, and 5-year survival rate. RESULTS: p53 protein nuclear staining was positive in 49 patients (62%). The mean PCNA LI was 55.6%, ranging from 3.35% to 92.9%. High PCNA LI (>55.6%) might contribute to higher 5-year survival rate, but it did not reach statistical significance (P = .09). Positive p53 protein staining and low PCNA LI were associated with the presence of locoregional recurrence. No statistical significance was found between p53 protein expression and PCNA LI and pathological subtypes and TNM stage. CONCLUSION: p53 protein and PCNA LI were not an ideal prognostic indicator in predicting 5-year survival rate in nasopharyngeal carcinoma. Future work will direct toward searching for other potential biomarkers with the hope to reinforce prediction of prognosis.