Detection of human papilloma virus in patients with squamous cell carcinoma of the esophagus planned for definitive chemo-radiotherapy, and a study of their clinical characteristics

Context: To identify the incidence of human papilloma virus (HPV) infection in squamous esophageal cancer. Aims: To identify high-risk (HR) HPV positivity rates in patients with squamous carcinoma esophagus and to compare their characteristics with HPV negative counterparts. Settings and Design: A prospective study, in which tumor biopsies of 18 consecutive patients with squamous carcinoma of the esophagus treated with definitive chemo-radiotherapy (CT-RT) were evaluated for the presence of HPV. Subjects and Methods: Tumor biopsies of 18 consecutive patients with squamous carcinoma esophagus treated with definitive CT-RT were assessed for presence of HR HPV DNA by hybrid DNA capture technique (Digene-HC2). The clinical characteristics and treatment outcomes of the two groups were then compared. Statistical Analysis Used: Pearson's Chi-squared test, Kaplan-Mier survival curve/log rank test. Results: Nine patients (50%) tested positive for HR HPV. The clinical features including age, gender, grade, location, and tumor extent were similar between the two groups. All the three patients with residual disease at the end of treatment tested positive for HPV (P = 0.058). At a mean follow-up of 52 weeks, the estimated median recurrence free survival was 37 weeks (95% confidence interval (CI): 13.6-60.4) among HPV positive patients compared to 53 weeks (95% CI: 29.6-76.4 weeks) for the HPV negative (P = 0.93). Conclusions: There appears to be a high incidence of HPV among patients with squamous oesophageal cancer in coastal Karnataka. Further studies are required to evaluate its causative role and prognostic implications.