Molecular testing of human papillomavirus in cervical specimens

OBJECTIVE: To improve the diagnosis of cervical neoplasia by early detection of human papillomavirus (HPV) in uterine cervix, by adding molecular testing of HPV using hybrid capture 2 (HC2) and polymerase chain reaction (PCR) tests to Papanicolaou (Pap) test.

METHODS: One hundred women were enrolled in this study. The mean age (mean ± SD) was 41.97 ± 8.76 years and the range was 27-65 years. All women had undergone cervical cytological screening with cervical cytology, HPV DNA testing by HC2 and PCR, during the period from January - December 2006, at King Abdul-Aziz University Hospital (KAAUH) and King Fahd Research Centre, Jeddah, Saudi Arabia.

RESULTS: The results we obtained by HC2 for detection of HPV were 5 (5%) high-risk HPV, one low-risk HPV (1%) and 94 (94%) negative cases. The PCR detected only 4 (4%) cases. Using the HC2 test as a reference, the sensitivity, specificity, positive predictive, negative predictive values and accuracy of baseline Pap were 50, 85, 17.7, 96.4, and 83%; of final Pap smear were 100, 96.8, 66.7, 100, 97%, and for PCR were 66.7, 100, 100, 97.9, and 98%. The Pap test was repeated within a year for patients with abnormal Pap or negative Pap test with positive HPV DNA.

CONCLUSION: Combined screening by cytology and HPV testing using both HC2 and PCR sensitively detects women with existing disease. The absence of HPV DNA provides reassurance that patients are unlikely to develop cancer for several years. We suggest using Pap with HC2 and PCR in screening programs to ensure that women with the double negative result at baseline might safely be screened at longer intervals.