The gastric cardia is not a target for human papillomavirus-induced carcinogenesis

Background: Thousands of people in central Asia die every year from gastric cardia adenocarcinoma (GCA). GCA arises in the transformation zone between the esophagus and the stomach, similar to cervical and oropharyngeal carcinoma, which arise in areas with transformation zone characteristics. The analogous biology of the gastric cardia to the cervix and oropharynx, where human papillomavirus (HPV) is known to cause cancer, raises the possibility that GCA could be a HPV-assodated cancer. Given the availability of an effective HPV vaccine and its potential to prevent HPV-associated cancer, we decided to evaluate the prevalence of HPV DNA in GCA. Methods: We collected tumor tissue from 144 histopathologically confirmed GCA patients at Yaocun Commune Hospital (Linxian, China), with rigorous attention to prevent DNA contamination. We tested for the presence of HPV DNA in fresh-frozen tumor specimens using PCR with sensitive L1-, E6-, and E7-based primers. Results: DNA was adequate, as indicated by β-globin positivity, in 108 cases. Of these, all (100%; 95% confidence interval, 97-100%) were negative for HPV DNA. Conclusions: These results suggest that HPV does not contribute to gastric cardia carcinogenesis in north central China. Impact: Because GCA does not seem to be a HPV-associated cancer, prophylactic HPV vaccination is unlikely to affect rates of GCA in China.