Prevalence Study of Esophageal HPV Infection in Patients with Megaesophagus and Correlation with in situ and 24-Hour PH Measurement

Introduction: Studies have clearly demonstrated an association between infection with human papillomavirus (HPV) and malignant epithelial lesions. This relationship seems to be well established for squamous cell carcinoma of the uterine cervix, for which highand medium-risk HPV types are associated with more than 95% of cases. A literature review correlating esophageal carcinoma with the presence of HPV demonstrated an association in 22.9% of cases when in situ hybridization was used and in 15.2% of cases when PCR was used for detection of the virus. The incidence of esophageal cancer has been shown to be 100 to 150 times higher among patients with megaesophagus compared to the general population. Methods: Fifty patients with megaesophagus ranging in age from 27 to 68 years (mean: 58.0) and 20 patients without esophageal pathology ranging in age from 52 to 70 years (mean: 59.9) were studied prospectively. In the study group, 29 patients were males and 21 were females. Primers specific for detection of HPV 16 and 18 used for the amplification of viral DNA by PCR. The measurement of in situ pH was performed using a SENTRON digital pH meter, with a scale of 1 to 14. 24-hour pH monitoring was conducted using the DIGITRAPPER MKIII, with the sensor probe positioned 5cm above the lower esophageal sphincter (LES). Results: HPV was detected in 19 (63.3%) of the 30 patients with megaesophagus studied, but in only three (16.7%) of the 18 controls, a difference that was statistically significant. HPV subtype 16 was detected in 15 cases. Positivity for HPV was significant in patients with megaesophagus and presented more percentage of time of pH in 24 hours between 5 and 6. Conclusions: These results demonstrate that the pH of the esophageal fluid ranges from 4 to 6 in patients with megaesophagus and shows a direct relationship with the presence of HPV. Subtype 16 was the most frequent HPV type.