Finding might one day improve rates of overtreatment, undertreatment in men, study says
WEDNESDAY, Sept. 11, 2013 (HealthDay News) -- A new gene test may help identify slow-growing prostate cancers that will require treatment, a new study suggests.
The test revealed the levels of "expression" of three aging-related genes and could be used to predict whether seemingly slow-growing prostate cancer will remain slow-growing, according to Columbia University Medical Center researchers.
Using the three-gene test along with existing cancer-staging tests could help doctors better determine which men with early prostate cancer can be safely monitored and spared the potential risks of prostate removal or other invasive treatments, the study authors suggested.
The investigators assessed the test in 43 prostate cancer patients who had been monitored for at least 10 years. All of the men had initially been diagnosed with low-risk cancer, but 14 eventually developed advanced prostate cancer. All 14 of those patients were correctly identified by the three-gene test, according to the study, which was published online Sept. 11 in the journal Science Translational Medicine.
The researchers plan to conduct a larger study to assess the test's accuracy.
"Most of the 200,000 prostate cancers diagnosed each year in the U.S. are slow-growing and will remain so, but the three-gene biomarker could take much of the guesswork out of the diagnostic process and ensure that patients are neither overtreated nor undertreated," study leader Cory Abate-Shen, a professor of urological oncology at Columbia University Medical Center, said in a university news release.
And, as study co-author Dr. Mitchell Benson, chairman and professor of urology at the medical center, explained in the news release: "The problem with existing tests is that we cannot identify the small percentage of slow-growing tumors that will eventually become aggressive and spread beyond the prostate."
Currently, men diagnosed with low-risk prostate cancer can choose either active surveillance, which includes regular testing and monitoring but risks missing the window when the disease is localized and potentially curable, or aggressive treatment, which can cause serious side effects such as urinary incontinence and impotence.
Dr. Louis Kavoussi is chairman of urology at North Shore-LIJ's Arthur Smith Institute for Urology in New Hyde Park, N.Y. He said: "Men getting a diagnosis of prostate cancer are initially shocked and begin conjuring images of themselves as desperate, dying patients. In reality, the majority of patients with prostate cancer do not die of the disease, and a large portion can be managed with observation. This study looks at novel molecular tools to help define which patients can be managed conservatively, and avoid potential side effects and expensive treatments."
Dr. Aaron Katz, chairman of urology at Winthrop-University Hospital in Mineola, N.Y., said: "In the current era, it is clear that PSA screening has detected many men with prostate cancer. In the years past, we believed that all men needed to be treated. The good news is that many men who are found to have these abnormal cells in their prostate may not need any treatment. With advances in genomics and DNA testing, we are now able to stratify those men with indolent disease, and prevent unnecessary treatment."
The U.S. National Cancer Institute has more about prostate cancer (http://www.cancer.gov/cancertopics/wyntk/prostate ).
SOURCES: Columbia University, news release, Sept. 11, 2013; Louis Kavoussi, M.D., chairman of urology, North Shore-LIJ's Arthur Smith Institute for Urology, New Hyde Park, N.Y.; Aaron Katz, M.D., chairman of urology, Winthrop-University Hospital, Mineola, N.Y.