The findings of a recent analysis indicate that a specific genomic abnormality found in either benign or malignant prostate tissues is predictive of the clinical outcome of prostate cancer.
As pathologist Jian-Hua Luo, MD, PhD, of the University of Pittsburgh (Pennsylvania) School of Medicine, and colleagues state in The American Journal of Pathology, the prediction of prostate cancer clinical outcome remains a major challenge, even with improved early detection by prostate-specific antigen (PSA) monitoring. But the group has discovered that a genetic abnormality known as copy number variation (CNV) in prostate tumors, in benign prostate tissue adjacent to the tumor (AT), and in the blood of men with prostate cancer can predict whether a patient will experience a relapse, and whether the relapse will be aggressive or indolent. CNVs are large areas of the genome with either duplicated or missing sections of DNA.
Luo’s team performed a comprehensive genome analysis on a total of 238 samples obtained from men undergoing radical prostatectomy: 104 tumor samples, 49 matched AT, and 85 matched blood. The investigators also tested three commercially available prostate cancer cell lines to validate the results.
Using gene-specific CNV from the tumor samples, the genome model correctly predicted 73% of the cases that would relapse and 75% of the cases that would show short PSA doubling time (less than 4 months). Using median-sized CNV from the tumor, those rates rose to 75% and 80%, respectively.
The gene-specific CNV model from AT correctly predicted 67% of the cases for relapse and 77% of the cases for short PSA doubling time. Median-sized CNV from the blood correctly predicted 81% and 69% of those cases, respectively.