Use of the same archival Papanicolaou smears for detection of human papillomavirus by cytology and polymerase chain reaction

An optimal method for the processing of archival cervical Papanicolaou (pap)-stained smears for the amplification of human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) was developed. This methodology was then applied to a series of 44 pap smears designated as HPV positive or negative (on the basis of both major and minor cytological criteria) or cervical intraepithelial neoplasia (CIN)-cancer. For the detection of HPV DNA, each sample was tested with the consensus GP5/6 primers, and when negative, with CPI-IIG primers. The HPV DNA was detected in 100% (8 of 8) of GIN-cancer smears using the GP5/6 primers. In smears with cytological evidence of HPV without CMI the use of both sets of primers yielded positive results in 100% (19 of 19) of the samples. Direct sequence analysis of PCR products showed that 16 of the 27 HPV-positive samples contained more recently described HPV types. When tested with both primer combinations, all 17 cytologically negative smears were positive for beta-globin but negative for HPV DNA. The findings show the value of using archival pap smears for further investigations to address issues such as latency, but they indicate that cytological criteria and DNA technology will be critical factors in the reliability of the results.