Test may help determine PCa surveillance candidates

A new genomic test for prostate cancer appears to help predict whether men are more likely to harbor an aggressive form of the disease, report researchers from the University of California, San Francisco.

The test, which improves risk assessment when patients are first diagnosed, can also aid in determining which men are suitable for active surveillance.

The authors found that the new test provides “statistically significant and clinically meaningful” prognostic information, and can help identify many more low-risk men who could safely choose surveillance. At the same time, the test can pinpoint men at apparent low risk who in fact may have potentially aggressive tumors, the authors said.

The independent UCSF clinical study of 395 men validated the Oncotype DX Genomic Prostate Score, a biopsy-based pretreatment tool of Genomic Health, Inc. as a predictor of high-grade or extracapsular prostate cancer.

“With the new test, we can more confidently recommend active surveillance when it is appropriate,’’ said lead author Matthew R. Cooperberg, MD, MPH. “And patients through active surveillance can avoid or delay surgery or radiation for their condition.”

In the UCSF study, which was presented at the AUA annual meeting in San Diego, investigators evaluated the ability of the 17-gene assay through prostate needle biopsy specimens to predict pathologic stage and grade at prostatectomy. The authors focused on whether the test’s biomarkers added independent predictive information beyond what could already be determined about a patient through standard PSA, Gleason grade, and biopsy detail variables.

The men in the study, identified from the UCSF Helen Diller Family Comprehensive Cancer Center Urologic Oncology Database, ranged from 38 to 77 years of age at time of diagnosis (median age, 58 years). The patients represented a range of low- and intermediate-risk tumors in terms of clinical risk characteristics.

Dr. Cooperberg and colleagues found that the test “contributed statistically significant, and clinically meaningful, additional prognostic information above and beyond existing, previously well-validated clinical risk stratification instruments.”

The authors noted a number of study limitations, including an explicit intention to include men whose tumors were expected to show a wider range of risk. Further, they said with additional study, the test might be used to identify men with particularly low-risk tumors who might be candidates for less-intense surveillance.

Genomic Health, Inc. performed the genomic tests described in the study and provided financial support to UCSF to help defray tissue, data processing, and pathology costs.