Self-collection of samples for HPV testing shows promise in detection of cervical cancer in Kenya
In Kenya, women face a cervical cancer mortality rate that is approximately 10 times as high as in the United States. A study by researchers at the University of North Carolina at Chapel Hill suggests that training women to self-collect genital samples to test for human papillomavirus (HPV), the causative agent of cervical cancer, can increase the coverage rates of cervical cancer screening. Higher screening coverage helps increase rates of detection of cervical lesions and ultimately treatment of the disease.
"The high mortality rate in Kenya is most likely attributable to a lack of cervical cancer screening and early treatment programs, as well as relatively high HIV prevalence. More concerted efforts need to be made to reduce cervical cancer, which is highly preventable," said Jennifer Smith, PhD, MPH, research associate professor at the UNC Gillings School of Global Public Health and member of the UNC Lineberger Comprehensive Cancer Center.
The study, published online by the journal Sexually Transmitted Diseases, collected data from 350 female sex workers in the Korogocho slum area of Nairobi from August 2009 to March 2011. Due to high HPV and HIV prevalence, these women have a higher risk of cervical cancer and associated high grade lesions than the general population. Recruited by community peer leaders at public meetings, participants attending the study clinic were first instructed to self-collect genital specimens for HPV testing using a brush provided by the study.
The self-collection was followed-up with a pelvic examination, where a physician collected cervical samples for Pap smear and HPV testing. The Pap smears were independently evaluated by two cytopathologists from the University of Nairobi, with discrepancies reviewed by a third. The HPV testing results showed strong agreement between the samples collected by the physician and those collected by the women themselves.
"In our study in Nairobi, women were able to follow the self-collection instructions, and the specimens collected by the women were of high quality. We compared physician- and self-collected samples for HPV testing, and our results show that HPV testing of the two sample types performed equally well in detecting high-grade lesions. These findings indicate that self-collection for HPV testing may be a viable means to increase cervical cancer screening coverage in low-resource regions," said the study's lead author Jie Ting, PhD, postdoctoral fellow in epidemiology at UNC.
HPV testing is effective in early detection of cervical pre-cancerous and cancerous tumors and is currently recommended for co-testing with Pap smear for women aged 30 years or older in the United States. In traditional clinical settings, collection of cervical specimens for HPV testing is performed by a physician.
"What will also be interesting is to look at how self-collection will work in a setting other than a clinical one. For example, if the women were to perform self-collection at home, how would that to compare to when she does it in the clinic?" said Ting.