Human papillomavirus infection and p53 mutation in esophageal squamous cell carcinoma and its impact on treatment outcome

Abstract

Introduction: Human papillomavirus (HPV) is emerging as a risk factor for esophageal squamous carcinoma. The prognostic value of the HPV status has been investigated. However, the results are much controversial. Aim: This study aims to document the association of HPV infection and mutation of p53 gene in esophageal squamous cell carcinoma (ESCC) and its impact on treatment outcome. Subjects and Methods: The study was conducted over a period of 12 months. A total of 30 cases of ESCC who were primarily to be treated with radiotherapy/chemoradiotherapy were included in the study. All the tissue samples for biopsy were subjected to immunohistochemistry to study p53 and p16 expression, which is a surrogate marker for HPV. The patients were treated by radiotherapy alone or concurrent chemoradiotherapy depending on performance status and stage of disease. The impact of p16 and p53 on overall survival (OS) and disease-free survival (DFS) was determined. Results: The median OS of HPV-positive patients was 22 months (95% confidence interval [CI] 12-31) as compared to 13 months (95% CI 7-18) for HPV-negative patients (P = 0.298). The median DFS for HPV-positive patients was 16 months (95% CI 7-24) as compared to 5 months (95% CI 4-6) for HPV-negative patients (P = 0.048). The median OS of p53-positive patients was 13 months (95% CI 6.7-19) as compared to 22 months (95% CI 12.7-31.2) for p53-negative patients (P = 0.080). The median DFS for p53-positive patients was 5 months (95% CI 3.7-6.2) as compared to 22 months (95% CI 15.7-29.4) for p53-negative patients (P = 0.014). Conclusion: Clinical findings of our result can be used to sum up that both HPV infection and p53 mutation status are reliable biomarkers and can help clinicians to predict treatment outcome and prognosticate patients better.