Issue link: https://viewer.e-digitaledition.com/i/425939
IN APRIL, THE FDA OPENED A SCHISM IN THE GYNECOLOGIC ONCOLOGY AND PATHOLOGY COMMUNITIES WHEN IT APPROVED THE ROCHE COBAS HUMAN PAPILLOMA VIRUS (HPV) TEST AS A PRIMARY SCREENING TOOL FOR CERVICAL CANCER. T RADITIONALLY, A THOROUGH preventive workup for cervical cancer included a Pap smear and HPV test performed in tandem. But the FDA decision has raised concerns about potentially unnecessary and harmful follow-up testing. While there's broad agreement that use of both Pap and HPV tests is an effective strategy for cervical cancer prevention, some observers point to the particular strengths of the cobas HPV Test. "A single Pap test misses between 50 percent and 75 percent of women with signifi cant cervical disease," says Thomas C. Wright Jr., MD, Professor Emeritus of Pathology and Cellular Biology, Columbia University, and a consultant for Roche. "In contrast, the cobas HPV Test detects over 90 percent of women with high-grade cervical cancer precursors." The Follow-up Concern In an unusual move, the FDA's decision also stratifies follow-up protocols, recommending colposcopy for women who test positive for HPV 16 and 18 — two strains responsible for many of the disorders related to the disease — and additional cytopathology tests for other high-risk HPV types. Approximately 79 million Americans are infected with some strain of HPV, and an estimated 14 million more are diagnosed each year, according to the CDC. The frequency of the infection and the fact that it often clears within two years without causing cancer have spawned warnings about possible overtreatment of young patients with invasive procedures, such as cervical punch biopsies and cone biopsies. Those procedures can lead to infertility, higher rates of preterm births and perinatal mortality, according to Anna E. Mazzucco, PhD, Scientifi c Advisor for the Cancer Prevention and Treatment Fund, one of more than a dozen organizations that oppose the FDA approval. Proponent s of t he approva l say it s st rat if icat ion of follow-up protocols safeguards against unnecessary testing by recommending colposcopy for women who test positive for HPV 16 or 18 — which are responsible for a large percentage of HPV-related cancers, according to the National Cancer Institute — and follow-up Pap smears for those who test positive for 12 other high-risk HPV strains. Keep Them Together? The ATHENA study — the clinical trial upon which the FDA based its approval — shows that the cobas HPV Test is effective and can potentially be better than primary Pap smears. But its advantages over co-testing are less certain. "Combining the two, you get a lot of information because you can detect the presence or absence of [HPV], and you can also look to see if any abnormal changes to the tissue are actually present," Mazzucco says. "Together, they can be a powerful combination, but they haven't been separated before in such a way that the HPV test would be done by itself. … It's important to have the Pap to inform positivity for the clinician in order to indicate if any further follow-up is actually necessary, especially because the follow-up can have risks that are very relevant to young women." ■ Finding Common Ground in the FDA's Cervical Screening Decision By Michael Ferguson SPECIAL CLINICAL SECTION: ONCOLOGY 2 2 | Long Island MD NEWS ■ M D N E W S . CO M