Instead, every three years is a reasonable timetable, according to the Preventive Services Task Force (USPSTF), the same group that recently recommended against routine prostate cancer tests for healthy men.
Proposing changes to 2003 recommendations, the task force also said evidence is still insufficient to weigh harms and benefits of tests screening for human papillomavirus (HPV) — in contrast with the views of cancer patient advocates, who on Wednesday stepped up their support of such tests.
However, in a rare show of unity, the groups including the American Cancer Society sided with the panel on the new recommendations and proposed new screening guidelines themselves for the first time, bluntly recommending against the common practice of annual Pap tests.
In a Pap test, cells are swabbed or scraped from the cervix to be examined for cancer or precancerous changes. The same cells can be used for HPV testing to analyze for presence of viral DNA.
“If you test every year you find a lot of benign infections that would go away on their own… You end up overscreening, overmanaging and overtreating women who are not actually at risk of getting cervical cancer,” said Philip Castle of the American Society for Clinical Pathology.
The task force, comprised of primary care physicians who are experts at evidence-based research, is a highly influential in setting the tone for primary care practice.
It must weigh the potential benefits of early detection of disease through screenings against the potential harms to healthy patients who may be subjected unnecessarily to more invasive procedures or side-effects.
Echoing the panels’ recommendations, the cancer groups also said women younger than 21 do not need to get tested.
“Everybody agrees on almost everything: Let’s get rid of regular annual Pap testing, let’s get rid of teenage screenings, let’s screen women who aren’t getting screened,” said Debbie Saslow, the American Cancer Society’s director of breast and gynecologic cancer.
Side effects of overtesting could include vaginal bleeding, pain, infections, risks of pre-term delivery and psychological impacts of facing a possible cancer diagnosis, experts say.
“If you get crazy about it, you’re going to harm most of the population, and that’s the paradigm shift… Screening is not about finding disease, it’s about ruling out disease in the primary healthy population,” Castle said.