Identifying certain tumor cells circulating in the blood of prostate cancer patients may be a non-invasive way of detecting cancer spread, according to a study presented at the recent National Cancer Research Institute (NCRI) Cancer Conference, held in Liverpool.
The study, “Capture of circulating tumour cells with epithelial and mesenchymal features for prostate cancer prognosis,” was conducted by researchers at the Barts Cancer Institute at Queen Mary University, and suggests that tests of circulating tumor cells expressing the mesenchymal marker vimentin may aid in predicting and monitoring prostate cancer progression.
Screening for prostate cancer now relies mainly on PSA tests and digital rectal exams, followed by prostate biopsies. But better approaches are required, particularly after health authorities started recommending against PSA tests to detect this cancer, based on reports that men with low PSA levels may also have prostate cancer.
“There’s a need to develop better tests to identify and monitor men with aggressive prostate cancer,” Dr. Chris Parker, chair of the NCRI’s Prostate Cancer Clinical Studies Group, said in a news release. “This research has found a promising new marker that could one day make it to the clinic to guide treatment decisions.”
Researchers studied samples from 80 men with prostate cancer, looking particularly for cancer cells that had undergone epithelial-to-mesenchymal transition, meaning that they now had the ability to migrate and invade organs elsewhere in the body.
Their results showed that blood samples with high numbers of such cells, identified by the expression of the vimentin protein, were more likely in samples collected from patients with more aggressive cancers, or whose cancer had spread.
This suggests that these cells may one day be combined with other monitoring techniques to monitor prostate cancer patients, and identify those at risk of metastasis.
“If we’re able to replicate these studies in larger groups of people, we may be able to one day predict the risk of someone’s cancer spreading so they can make more informed treatment decisions,” Parker said.
Prostate cancer in the second most common male cancer in the U.S., with more than 180,000 new cases expected in 2016 alone, according to estimates from the American Cancer Society. In the U.K., about 46,500 new cases are diagnosed each year.