(RxWiki News) Not all prostate cancers even need to be treated, but many men receive more treatment than necessary. New research may change that trend.
Researchers have discovered that five inherited genes influence and predict the aggressiveness of prostate cancer. These findings may lead to a blood test that could be given at the time of diagnosis to help determine the most appropriate course of treatment.
"Ask your oncologist which treatment is best for you."
So-called indolent tumors are known to rarely progress to become life-threatening. Yet many men with these types of malignancies undergo aggressive therapy that can cause a number of serious side effects.
Such overtreatment is not only burdensome to the individual men and their famiies, but the healthcare costs for these therapies reach into the billions each year.
To learn more about appropriate ways to treat various stages of prostate cancer, scientists have been searching for biomarkers that can tell the difference between indolent and aggressive tumors.
An international study, involving scientists from the United States and Sweden, has accomplished this goal.
Janet L. Stanford, Ph.D., co-director of the Hutchinson Center's Program in Prostate Cancer Research and a member of its Public Health Sciences Division, led the American team. She says a panel of biomarkers has been identified that indicate and predict disease aggressiveness.
These markers are called single-nucleotide polymorphisms or SNPs ("snips") that influence the progression of prostate cancer.
For the study, investigators analyzed blood sample DNA gathered from 1,309 prostate cancer patients in Seattle, aged 35-74. A total of 22 SNPs were found that were associated with aggressive forms of the disease.
These SNPs were validated in the Swedish study involving 2,875 prostate cancer patients of the same ages.
Additional study narrowed the field to five SNPs and five genes that were most commonly seen in lethal cancers. These genes are: LEPR, RNASEL, IL4, CRY1, ARVCF.
Patients who had the most (four or five) of these genes had a 50 percent greater risk of dying from prostate cancer than men who had fewer of these genes.
Stanford says this study is the first to identify genetic markers associated with lethal prostate cancer.
Additional studies are planned to learn more about how this panel may be used to predict the course of the disease and its treatment.
This study is published in Cancer Epidemiology, Biomarkers and Prevention.