Orlando, FL—An independent review of the literature suggests that 3 biomarker tests developed for prostate cancer have yet to justify their utility in randomized clinical trials. The 3 tests in question—Prolaris, Decipher, and Oncotype DX for prostate cancer—are being used in practices around the country, cost approximately $3500 per test, and are reimbursable by Medicare depending on the state.
“These are promising tests, but they need future testing for clinical applicability, and this testing can be done by incorporating them into randomized clinical trials,” stated Meghan Anastasia Cooper, MA, MS-IV, a fourth-year medical student at Lake Erie College of Osteopathic Medicine, Bradenton, FL. Ms Cooper presented these findings at a poster session during the 2015 Genitourinary Cancers Symposium.
Most of the studies on these tests are sponsored by the companies that market them. Ms Cooper and colleagues screened the medical literature and found 32 studies of these tests. Only 8 met the criteria of adequate sample size for reliable statistical analysis, original and validation studies, utilizing data sets from independent patient cohorts, and studies reporting appropriate statistical evaluations.
Hazard ratio, odds ratio, area under the curve, or precision and reproducibility were used to quantify the assays’ predictive capability.
“It is difficult to compare directly performance of these 3 tests, and no prospective studies have been reported to validate these assays,” Ms Cooper stated.
Prolaris (Myriad Genetics) and Oncotype DX for prostate cancer (Genomic Health) are used on the biopsy specimen to identify the presence of a gene panel, and both tests are being marketed to identify low- and very low-risk men who can be managed by active surveillance, theoretically preventing overtreatment and saving the healthcare system money.
Decipher (GenomeDx Biosciences) is a genomic test that is used on the prostate specimen after radical prostatectomy, and the test can predict aggressive disease or less aggressive disease, thereby helping physicians to choose the most appropriate postsurgery management.
