Human papillomaviruses (HPV) possess the ability to induce cervical intraepithelial neoplasia. Fourteen HPV genotypes are classified by IARC as being group 1 carcinogens, or high-risk HPV types. It was noted that other HPV types were identified as single HPV infections in certain rare cases of cervical cancer (HPV26, 53, 67, 70, 73, 82), termed potential high-risk HPV types. In general, HPV67 has only been limited subject of research. Therefore, the objective of this study was to explore the epidemiology of HPV67 in a general screening and diagnostic population of Belgian women. Furthermore, cyto-virological correlation between HPV67 and the different cytological categories was explored.
Samples were analyzed using a high-throughput type-specific TaqMan-based real-time quantitative PCR. In total, 478.822 samples were evaluated between 2009 and 2015 for presence of HPV67. There were 375.988 samples collected from a preventive screening population and 102.834 samples from women in a diagnostic follow up.
Overall, HPV67 was found in 1,85% of the examined samples. A significant higher prevalence was found in the diagnostic population (4,11%) compared to the screening population (1,22%). In 48,64% of the HPV67 infected women from the preventive group, it was detected as a single infection. In the diagnostic population, the proportion of HPV67 single infections was 35,17%. According to cytological categories, HPV67 was found in 0,75% of Negative for Intraepithelial Lesion (NILM); 6,34% of Atypical Squamous Cells of Undetermined Significance (ASC-US); 7,81% of Low-grade Squamous Intraepithelial Lesion (LSIL); 5,71% of ASC-cannot exclude HSIL (ASC-H); 5,60% of High-grade SIL (HSIL) and 9,09% (1/11 cases) of cancer cases in the screening population. In the diagnostic group 2,66% of NILM; 6,90% of ASC-US; 7,66% of LSIL; 5,12% of ASC-H; 4,91% of HSIL and no cancers cases were found to be HPV67 positive. During microscopic examination, 1.034 samples were diagnosed as Atypical Glandular Cells (AGC). Within this category, HPV 67 appeared to be present in 1,84%. In more than half of these cases, HPV67 was found to be a single infection (57,89%). This phenomenon was discovered to be more pronounced in the screening (71,43%) versus the diagnostic (50,00%) population. The only HPV67 positive cancer case was categorized as a cervical adenocarcinoma, albeit in combination with other HPV genotypes.
The non-negligible prevalence of HPV67 indicates that further investigation and study on epidemiology is required for the understanding of its role in the genesis of cervical cancer.
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