Evidence Against a Role for Human Papillomavirus in Colon Neoplasms

To the Editor . —In the article by Kirgan et al 1 in the July 1990 issue of theArchives, the authors note that human papillomavirus (HPV) antigen and DNA were present in a large percentage of colon carcinomas, normal colonic mucosa, and benign colon tumors. These findings are the opposite of what has been described by others in the genital tract and colon. Human papilloma-virus DNA and HPV antigens are rarely found in normal genital tract tissues using in situ hybridization or immunohistochemistry. 2,3 Further, when the antigen is detected, the DNA is invariably also detected. Using more sensitive techniques (Southern blot analysis and the polymerase chain reaction, which can detect as few as 10 viral particles per million cells compared with 10 viruses per cell with the in situ method), several investigators have not been able to detect HPV DNA in colon tumors. 4,5 When the results from these