October 16, 2002
Some of the more than 100 strains of HPV cause warts on the hands, feet, mouth or genitals, while others have no symptoms. Certain sexually transmitted strains of HPV are already believed to be the major cause of cervical cancer, but there is also evidence that HPV may contribute to other cancers, including vaginal and penile cancers and some cancers of the head and neck. Esophageal cancer is relatively rare in many parts of the world. But certain regions, such as parts of China, have unusually high rates of the disease.
The study looked at one Chinese region, Eastern Guangdong, where esophageal cancer is common. Researchers found that among the 55 esophageal cancer patients they studied, certain strains of HPV were commonly found in tumor samples. Dr. Zhong-Ying Shen of Shantou University Medical College and colleagues reported the findings in the November issue of the Journal of Medical Virology, "Detection of Human Papillomavirus in Esophageal Carcinoma" (2002;68:412-416). Overall, HPV was found in more than 60 percent of both cancerous and normal tissue samples taken from the patients. But two "high-risk" strains tied to cancer, HPV 16 and 18, were found mainly in tumor samples, Shen's team reports.
"Our results," the researchers write, "suggest that the high incidence of esophageal carcinoma in this particular region may be associated with the high infection rate with HPV, and HPV may be one of the major risk factors in the development of this tumor." They note that in past studies in areas with low rates of esophageal cancer, HPV has either not been detected or has shown up far less often in esophageal tumor samples. Smoking and heavy drinking are among other factors believed to raise the risk of esophageal cancer.