Good Article: New cervical cancer screening test raises hope, concern

Cervical cancer screening used to be simple: Women visited their gynecologist every year for a Pap smear.

But that ritual has become more complex as science and technology have allowed researchers to better understand and detect the disease. Now women have a newer option that combines the Pap with additional DNA testing plus the first federally approved alternative to the Pap.

“There’s definitely confusion from the patient perspective because for many, many years we, as women, were told to come in and have a Pap smear every year. But in the past 10 to 15 years, our knowledge about cervical cancer and what causes it has improved,” said Dr. Ruth Goldenberg, chief for obstetrics and gynecology for the Kaiser Permanente region that includes Napa and Solano counties.

The tried-and-true Pap smear has been responsible for reducing U.S. cervical cancer incidence and deaths by more than 60 percent since the 1950s, according to the National Institutes of Health.

Then in 2012, with the advent of molecular testing, U.S. screening guidelines were updated to include testing for HPV, or the human papillomavirus, which is responsible for almost all cervical cancers. Rather than relying on a test that involves examining cervical cells through a microscope, HPV testing looks for the presence of the virus that causes cervical cancer. It’s much more objective and, according to health experts, more accurate than the Pap alone.

The new guidelines recommend women either get the Pap alone every three years or the Pap-HPV combo every five years if the most recent results are normal.

Something else new

Now, even newer tests are being added to the mix. In April, the U.S. Food and Drug Administration approved an HPV test that can be used exclusively in place of the Pap as the primary screening tool for cervical cancer. The test was developed by Roche Molecular Diagnostics in Pleasanton.

“We worked very hard for last 50 years to imbue women with the importance of getting a yearly Pap test. Now we’re changing the game,” said Dr. Paul Blumenthal, a Stanford gynecology and obstetrics professor and director of the Stanford Gynecology Service.

The new HPV-only test has raised concerns, particularly by women’s health groups, that replacing the stalwart Pap complicates what already is an evolving key cancer-prevention area for all women.

Most gynecologists say the Roche test, called the cobas HPV test, probably won’t change testing immediately. It’s still very new, and no major medical groups are recommending HPV testing alone for cervical cancer screening yet.

The new Roche test does have allies who see the Pap, which requires doctors to look at cervical cells through a microscope, as subjective and outdated.

“If the Pap smear came before the FDA today, it probably wouldn’t be approved,” Blumenthal said.

The Pap catches the majority of cervical cancers, but is notoriously inaccurate. It is associated with a lot of false positives and false negatives, meaning women are often called back for additional tests. Annual screenings had been recommended because of a 30 percent chance a single test might not be right.

Pap-HPV gains favor

Over the past decade, even before the American Cancer Society and other medical organizations issued the guidelines, doctors and health care organizations had been turning to the Pap-HPV “co-test” because research has shown the combination is better at detecting the strains of HPV that are more likely to lead to cancer.

But a drawback to HPV testing is that almost everyone who has had sex has been exposed to HPV. Most people’s immune systems will get rid of the virus within a few months or up to several years. As a result, a single positive HPV test is typically not a concern to physicians.
Source: http://www.sfgate.com/health/article/New-cervical-cancer-screening-test-raises-hope-5526310.php