(RxWiki News) The current most widely used test for detecting and monitoring prostate cancer, known as prostate specific antigen (PSA), has a lot of room for improvement for detecting new cancers.
Several new tests are in development to replace PSA, trying to be both sensitive to small changes as well as specific to only cancer.
A new candidate for replacing PSA has shown success in the first extensive trial run in patients.
"Ask your doctor about prostate screening tests."
Researchers from the University of Pittsburgh documented that the new test diagnosed prostate cancer 75 percent of the time, and correctly predicted relapse 73 percent of the time.
The test works by taking cells from a prostate biopsy, and counting the number of abnormalities in the DNA, resulting in a number called copy number variation (CNV).
CNV refers to an unusual amount of duplicated areas in the DNA, and generally indicates that something has gone wrong in the cell.
Using the CNV from prostate cells, the test correctly predicted 75% of prostate cancers and 73% of cancer relapses.
Lead investigator Jian-Hua Luo, MD/PhD, pathology professor at the University of Pittsburgh School of Medicine says his results show that this test would be enormously helpful for urologists looking at questionably cancerous prostates by showing the level of abnormality in the DNA of the tumor.
“For a patient diagnosed with prostate cancer, CNV analysis done on blood or normal tissues would eliminate the need for additional invasive procedures to decide a treatment mode."
For a patient already having a radical prostatectomy, CNV analysis on the tumor or blood sample may help to decide whether additional treatment is warranted to prevent relapse.
"Despite some limitations, including the need for high quality genome DNA, CNV analysis on the genome of blood, normal prostate, or tumor tissues holds promise to become a more efficient and accurate way to predict the behavior of prostate cancer.”
Dr. Luo hopes to develop his test for commercial use, but further testing, with a larger population, is needed to refine the science.
The study used 238 samples from men with abnormal prostates, including 104 direct tumor samples, 85 blood samples, and 49 benign prostate samples. Researchers then double-checked their results using three different prostate cancer cell lines from laboratories.
The study was published in the American Journal of Pathology online on May 6, 2012.
This research was supported by grants from the American Cancer Society, the National Cancer Institute and the University of Pittsburgh Cancer Institute.