Home-based Self-collected Vaginal Specimens Detect More Cervical Lesions and Cancers Than Cytology

Vaginal Self-collection for Hybrid Capture(R)-based HPV Testing Increases Screening Coverage and is More Sensitive than Pap Smear Shows a Mexican Study Published Today Online in the Lancet
Promising findings published today online in the Lancet from a community-based, randomized equivalence trial undertaken by public health authorities in Mexico to investigate DNA home testing for human papillomavirus (HPV) compared with cytology (evaluation of cells) based on Pap smears. The study indicated that the relative sensitivity of HPV molecular testing was 3.4 times higher than cytology. Additionally, 4.2 times more invasive cancers were detected. The home testing study adds support to previous evidence that adding self-collection to the screening setup can increase the coverage rate of cervical cancer prevention programs, especially in underserved regions in developing and developed countries. The study was funded by the Instituto Nacional de Salud Publica (INSP), the Health Ministry of Mexico and QIAGEN.
"HPV testing is lower in cost, easier to implement, and has lower false-negative rates than cytology. Testing of self-collected vaginal samples offers increased coverage and acceptability," commented the lead study author, Dr. Eduardo Lazcano-Ponce, professor at the Centro de Investigacion en Salud Poblacional of INSP in Morelos, Mexico.
The trial included 25,061 women of low socioeconomic status between 26 to 65 years from 540 rural communities in Morelos, Guerrero, and Mexico State, Mexico. They were randomly allocated to HPV DNA testing of a vaginal sample self-collected at home or cervical cytology at the nearest health center. Eight community nurses visited the self-collection women at home and instructed them how to use the digene(R) cervical sampler, a conical-shaped brush, to take the sample. The study used the digene(R) HPV test based on Hybrid Capture 2, which is considered the gold standard for HPV testing and already has been clinically validated in trials including more than one million women worldwide. The primary endpoint was CIN2 or worse, detected by colposcopy. Any woman having a positive result for either of the tests was referred to colposcopy.
The participation rate was higher in women randomized to the HPV group (9,202 of 9,371, 98%) than in the cytology group (11,054 of 12,731, 87%). Importantly, in the HPV group more invasive cancers were detected than with cytology (28 vs. 8). With a lower positive predictive value for HPV testing (PPV CIN2 or worse 12.2% vs. 90.5%) the identification of appropriate triage methods is crucial. The study adds: "Because women at these sites will be screened only a few times in their lives, the high sensitivity of a HPV screen is of paramount importance."
Based on data from several national trials including Hybrid Capture technology, Mexico is the first country to implement frontline HPV testing with cytology triage as a national cervical cancer prevention program. Dr. Nubia Munoz, Colombian Cancer Institute, Bogota, Colombia, and Dr. Rolando Herrero, Prevention and Implementation Group, International Agency for Research on Cancer, Lyon, France, conclude in an accompanying editorial in the Lancet: "The experience shows what can be achieved when scientific judgment guides public health policy."
"The value of HPV DNA testing in cervical cancer screening and disease detection has been proven again and again for both the developed and developing worlds. Self-collection for HPV DNA testing could become an important way for national cervical cancer prevention programs worldwide to increase coverage rates," said Dr. Helge Lubenow, Head of the Molecular Diagnostic Business at QIAGEN. "Our digene HPV testing solutions have been used in several trials for self-collection, and we support any approach that helps to include populations that are difficult to reach as here are most cases of cancer to be found."