The Pap test has been the standard screening tool for cervical cancer for years — and it still is. The test checks a sample of cervical cells under a microscope for abnormalities that may lead to cancer.

Lessons learned in the past several years are leading to changes in recommended screening frequency, and a new test is under study, according to the April issue of Mayo Clinic Women’s HealthSource.

First, Pap tests don’t need to be a yearly event for every woman. The American Cancer Society recommends that women over 30 who’ve had normal Pap results for three years can limit screening to once every two or three years. Women over age 70 who’ve had three normal tests in a row, no abnormal tests in 10 years and no new risk of cervical cancer (such as a new sexual partner) can opt to forgo cervical cancer screening.

Researchers are evaluating a human papillomavirus (HPV) screening as a way to detect cervical cancer earlier. Like the Pap test, the HPV test is conducted on a sample of cells collected from the cervix. The test looks for evidence of the HPV genetic material that can lead to cancer.

Two studies published in 2007 showed that the HPV test has promise. One found that the HPV test was nearly 40 percent better at identifying women with precancerous or cancerous abnormalities than the Pap test. The second study looked at using HPV and Pap screens together. This approach helped identify causes of precancerous lesions earlier than the Pap alone.

There are concerns with the HPV screen, too, including a higher percentage of false-positive results, where women who received positive HPV tests were referred for further tests that did not show any signs of cancer. HPV screening also identifies more precancerous lesions that are slow to develop into cancer or never develop into cancer.

For now, most doctors don’t support HPV testing as a primary screening tool until there’s more evidence to justify replacing the Pap test. Depending on a woman’s age and risk factors, the HPV test may be ordered after an uncertain Pap test or, in some circumstances, may be used in conjunction with a Pap test. Women should ask their doctor which screening is best.

News source

In a new collaborative study, the BC Cancer Agency, an agency of the Provincial Health Services Authority (PHSA), is trying to determine if a test for Human Papilloma Virus (HPV) can replace the standard Pap test as the primary method of cervical cancer screening, allowing women to be screened more effectively and less frequently.

The HPV FOCAL Study – the first long term and largest study of its kind in North America is conducted in collaboration with another PHSA agency, the BC Centre for Disease Control, as well as the UBC Department of Family Medicine and the Faculty of Medicine, McGill University department of Epidemiology, and about 100 family doctors in Greater Vancouver.

“Over the last 20 years, it has become apparent that infection from HPV is the primary cause of cervical cancer,” says Dr. Andy Coldman, BC Cancer Agency Vice President of Population Oncology, and Principal Investigator of the study. “If we can test for the presence of high-risk strains of this virus, we believe we can identify women who are truly at risk for developing cervical cancer and its precursors.”

“If HPV is found, we know a woman may be at higher risk. We can then further analyze her cervical sample with Pap testing in the laboratory to see what treatment, if any, she may require,” adds Dr. Coldman.

The study aims to enroll 33,000 participants over the next seven years. Women age 25-65 who attend one of the over 100 participating family practices will have the opportunity to be part of the study. Participants will have a cervical sample taken by their family doctor during their regular screening appointment, with appropriate follow-up depending on the test results. The sample is collected from a woman the same way as a Pap smear is obtained – the only difference is how the sample is processed in the laboratory.

The Pap test requires technicians to examine samples under a microscope to look for abnormal cells. The HPV test is read by a machine that detects presence or absence of DNA for high-risk strains of HPV.

“The Pap test is an effective screening tool, but it’s not perfect,” adds Dr. Coldman. “We believe the HPV test is superior to the Pap test as a screening tool, but its true benefits are still unknown until we
To compare HPV testing to the Pap test, cervical samples from study participants will be randomly assigned to one of the following testing methods:

- Pap test (using a liquid based collection medium)
- HPV test, and screened again in two years if no HPV is found
- HPV test, and screened again in four years if no HPV is found

For Janet Abe, whose parents were both diagnosed with cancer within three months of each other six years ago, taking part in a study that could help improve cancer outcomes in the future was an easy decision.

“This was really a no-brainer,” says Abe, a 38-year-old magazine production manager. “It’s so simple. I would be going for my regular Pap test anyway, but now I can participate in a study that could potentially make a difference for women and their families down the road.”

News sourse