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Human papillomavirus 16 and 18 infection is absent in urinary bladder carcinomas.

OBJECTIVE
The role of human papillomavirus (HPV) in the pathogenesis of bladder neoplasia remains controversial. Studies to date have mainly utilized polymerase chain reaction and DNA blot techniques to detect HPV DNA. The detection rates have varied from 0 to 81%. One of the major limitations of these techniques is that they lack topographic information. We have used a highly sensitive in situ hybridization (ISH) technique which detects single copies of viral genome and provides topographic information for investigation of HPV infection in bladder carcinomas.


MATERIALS AND METHODS
Thirty-one samples of formalin-fixed paraffin-embedded bladder carcinomas (4 adenocarcinomas, 5 squamous cell and 22 transitional cell carcinomas) were examined using non-isotopic ISH with biotin-labelled DNA probes of HPV 16 and 18 subtypes. HPV-positive skin and anal carcinoma samples were used as controls.


RESULTS AND CONCLUSIONS
No positive signals for HPV 16 or 18 were detected in any of the bladder carcinoma samples. Given the sensitivity of the technique, the result indicates that HPV 16 and 18 are not implicated in the development of bladder neoplasia compared to certain other epithelial malignancies. The possibility that other subtypes of HPV contribute to bladder epithelial carcinogenesis remains to be clarified.