DETECTION OF HPV DNA IN NEOPLASTIC AND NONNEOPLASTIC CERVICAL SPECIMENS FROM PAKISTAN AND JAPAN BY NONISOTOPIC INSITU HYBRIDIZATION

In order to determine the prevalence and type-specific distribution of human papillomavirus (HPV) in women from Pakistan, a country with a low cervical cancer rate (hospital-based data), and to compare these results with their counterparts in Japan, we studied 56 non-neoplastic cervical tissues and 162 cervical carcinoma cases from both countries. HPV infection was defined by in situ hybridization in paraffin-embedded tissues using biotinylated HPV 6/11, 16 and 18 probes. The overall positivity rates in non-neoplastic and neoplastic cervical tissues from Pakistan were 33% and 88%, while in those from Japan the rates were 46% and 80%, respectively. High-risk HPVs (16 & 18) were found in 17% of the non-neoplastic specimens and in 69% of cervical carcinoma cases from Pakistan, while Japanese figures in this respect were 19% and 68%, respectively. No correlation was found between the type-specific distribution or prevalence of HPV and the geographic location of the cases examined in the 2 countries. However, in comparison to Japanese women, the incidence of HPV-16-positive cervical carcinoma in Pakistani women decreased significantly (p < 0.05) in the oldest age group as compared to the youngest age group.