By Kristen Mitchell
A George Washington University researcher was awarded more than $1.81 million by the National Institutes of Health and the National Cancer Institute to explore several biomarkers that could lead to a better approach for anal cancer screening.
Jeanne A. Jordan, professor in the department of epidemiology and biostatistics in the Milken Institute School of Public Health, believes combining one or more of these biomarkers with the anal Pap test might improve the specificity of the screening approach and provide physicians with a higher degree of confidence when recommending patients get an invasive biopsy.
Anal cancer is a growing problem among men who have sex with men. Such men, especially if they are living with HIV, are also at higher risk of being unable to clear infection with the human papillomavirus (HPV). Certain types of HPV are known to cause anal cancer.
Currently when a man living with HIV goes to a doctor for screening, he undergoes an anal Pap test, which looks for abnormal changes in cells. To improve the chances of identifying someone at high risk for anal cancer, physicians will sometimes also test for an HPV infection.
That test is good at identifying an HPV infection but doesn’t predict the risk of developing anal cancer. Thus the combined anal Pap test plus HPV test in its current form sends too many men on for an unnecessary and invasive biopsy to check for anal cancer.
Dr. Jordan and her team are going to test some alternate biomarkers that when used along with the anal Pap test might lead to a more effective screening for this kind of cancer. For example, the team will look at the expression of certain HPV genes or protein products along with changes in the HPV genome that can trigger out of control cell growth and anal cancer.
Men who tested positive with the improved combo method would be considered at higher risk for developing anal cancer—and only that subgroup would then go on to have a biopsy taken.
Dr. Jordan hopes the method might mean a reduction in the number of men unnecessarily sent on for the invasive testing. At the same time, the new testing method could be used to screen men and quickly identify those who do need to get a definitive biopsy, which can reveal cancerous or even pre-cancerous lesions.
If the biopsy is positive, doctors could remove the lesions, a step that could prevent anal cancer. Or if the biopsy finds an outright anal cancer, then it could be treated and sometimes cured if caught early enough.
Dr. Jordan and her team plan to analyze samples obtained from 250 men living with HIV who are being treated by Stephen Abbott, a physician at Whitman-Walker in Washington, DC.
“The goal of this grant was to design experiments that will hopefully lead us to identifying a more specific companion diagnostic to the anal Pap test,” she said.
The researchers hope to have a combination screening test that is more accurate than the current screening method identified by the end of the five-year study.
