Self-sampling: New option for HPV screening

Genital human papillomavirus is the most common sexually transmitted infection in the United States and is thought to be responsible for more than 99% of cervical cancers.

HPV screening usually entails a speculum-based exam, which is an uncomfortable experience for most patients, especially those who have physical disabilities.

In two studies, published in Preventive Medicine Reports and JAMA Network Open, University of Michigan researchers are the first to demonstrate in the U.S. that self-sampling is just as effective as speculum-based testing for HPV detection.

Most people who have HPV are usually unaware that they have it. 

By age 50, at least 4 out of 5 women will have been infected with the virus at some point in their lives.

Usually, these infections disappear within 2 years, due to the body's defenses. However, in some women the infection lingers and puts them at risk for cervical cancer.

Currently, cervical cancer screens and HPV testing is recommended for women every 3 to 5 years starting at age 25.

Co-testing for HPV and cervical cancer is not useful in any meaningful way. You can find the same occurrence of cervical cancer and its precursors by just testing for HPV alone."

Diane Harper, M.D., Study Senior Author and Professor, Obstetrics and Gynecology, Family Medicine and Women's and Gender Studies, University of Michigan

Additionally, the entire process can be physically and emotionally taxing.

"Half of the women in the U.S. who have cervical cancer did not undergo a screening test in the past ten years. We should try to make it a more comfortable experience," Harper said.

Several countries, including Sweden, Australia and the Netherlands, that have adopted self-screening for HPV have also reduced their incidence for cervical cancer.

"We wanted to focus on the U.S. population and compare self-sampling to speculum-based HPV testing," Harper said.

Vaginal swabs are useful for first-line HPV screening

The researchers used a cohort of 193 people, between 25 and 65 years, who were either undergoing a routine screening or were at risk for cervical cancer. 

"Half of the women in the US who have cervical cancer did not undergo a screening test in the past ten years. We should try to make it a more comfortable experience," Diane Harper added.

The study participants were instructed to use vaginal swabs, which were then collected and sent to the laboratory. They also underwent speculum exams.

All the samples were tested for 15 types of high risk HPV types.

"We found that using swabs is equivalent to speculum-based collection," Harper said.

The team also found that their results were in agreement with global data on HPV prevalence, reinforcing the usefulness of vaginal swabs.

Self-sampling improves screening experiences for those with physical disabilities

"Women with physical disabilities have lower rates of cervical cancer screening due to several barriers, including inaccessible healthcare facilities, healthcare providers misunderstanding their risk for cervical cancer and difficulty with positioning for a speculum exam," said Susan Ernst, M.D., a clinical associate professor of obstetrics and gynecology and an author of one of the studies.

Using a cohort of 56 women who had physical disabilities, the researchers tested whether they also preferred vaginal swabs over speculums.

"I was already aware that speculum-based exams can sometimes be unpleasant. However, some of the experiences the participants shared with us were truly horrifying," said Corrianne Norrid, a medical student at U-M Medical school and co-first author of the study.

The women described in-office speculum-based screenings as "cold", "traumatizing" and "invasive". However, when asked about the at-home self-sampling, the women described the experience as "simple", "comfortable", and "feasible".

"The swabs cannot replace having a conversation with your doctor. However, it can save the vast majority of women from getting unnecessary speculum tests," Harper said.

The researchers are working with U-M Health to make self-sampling the primary method for cervical cancer screening in their clinics.

The researchers hope that results from both studies will inform education and promotion efforts to all people.

"This is a great example of how multiple disciplines at Michigan Medicine work together," Harper said. 

"Our next goal is to find a cure for HPV."