Hormuzd Katki, PhD
The first large-scale study of both human papillomavirus (HPV) testing and Pap smear for cervical cancer screening in routine clinical practice confirms that women can safely extend their screening intervals from 1 to 3 years, according to information released today in a press briefing of the American Society of Clinical Oncology (ASCO). These findings may redefine current screening guidelines.
In the past 30 years, scientists have determined that HPV causes every case of cervical cancer, according to lead study author, Hormuzd Katki, PhD, the principal investigator in the Division of Cancer Epidemiology and Genetics at the National Cancer Institute.
“The results of this study suggest that an HPV-negative test result alone could be enough to give a high level of security for extending the testing interval to every 3 years, but we’ll need additional evidence from routine clinical practice, and formal recommendations from guideline panels before that can be routinely recommended,” he said. According to Katki, a series of guideline committee meetings will occur later this year and over the next year, representing over 20 organizations on the potential value of HPV testing.
The FDA has approved the vaccines Gardasil (2006) and Cervarix (2009) for the prevention of diseases caused by HPV, including cervical cancer. The agency has also approved both the digene
HPV Test, the first FDA-approved test that screens for the presence or absence of oncogenic HPV types, and the Roche cobas HPV Test. These advances have pushed the establishment of definitive guidelines to help eradicate cervical cancer at the forefront of gynecologic oncology.
Screening guidelines from the American College of Obstetricians and Gynecologists and the American Cancer Society endorse the use of concurrent HPV testing with Pap as a safe alternative to Pap testing alone for women aged 30 years or older. They recommend co-testing every 3 years for women who are HPV negative with a normal Pap test. However, this practice has not been widely adopted, according to an ASCO press release. The data presented today provides substantial evidence to confirm the safety of this practice.
Researchers followed 331,818 women, aged 30 years and up who enrolled in Kaiser Permanente Northern California’s co-testing program between 2003 and 2005 for 5 years. Researchers found that the 5-year cancer risk for women with normal Pap test along with a negative HPV test was 3.2 per 100,000.
Katki presented data that concluded that a single negative HPV test provided 5 years of extremely low cancer risk for women, and that a Pap test does not appreciably lower this risk. “Instead of cotesting, where women are testing with both test in each visit, we would instead screen with HPV testing first and then Pap testing only reserved for the HPV positive women,” Katki said.
Mark H. Einstein, MD, MS
“Ultimately the goal is to eradicate cervical cancer. Starting with the more sensitive test, HPV testing, then moving to the more specific test, [the] Pap test, would enrich the Pap tests to those most at risk for cervical precancerous lesions and cancer,” said leading expert Mark H. Einstein, MD, MS, associate professor of the Departments of Gynecological Oncology and Epidemiology & Population Health at the Albert Einstein College of Medicine.