Originally published Dec. 13.
Genomic Health last week released initial data from a large prostate cancer study that correlated hundreds of genes with the likelihood that a patient's prostate cancer will recur.
The data is the first that the company has released for a prostate cancer recurrence test it is developing. Steven Shak, chief medical officer at Genomic Health, said in a statement that the results "give us confidence to move forward with full clinical development, and we are evaluating the opportunity to accelerate these efforts with our scientific advisors."
A Genomic Health spokesperson told PGx Reporter that the company expects to provide more information early next year on the timing for future studies and the eventual launch of the test.
Genomic Health Chief Financial Officer Brad Cole previously noted that the firm's next "big" test opportunity after its flagship Oncotype DX breast cancer recurrence test would likely be a test gauging prostate cancer recurrence. As many as 1 million men have biopsies each year, and 200,000 men are diagnosed with prostate cancer annually, according to company estimates (PGx Reporter 09/29/10). Prostate cancer is the second leading cause of cancer death in men in the US.
In the preliminary study results reported last week, researchers from Genomic Health and Cleveland Clinic analyzed RNA from 431 prostate cancer patients who had previously had a radical prostatectomy at the Cleveland Clinic between 1987 and 2004. Within this cohort, the researchers identified 295 genes that "strongly associated with clinical recurrence following radical prostatectomy." The study used the same real-time PCR-based Oncotype DX platform on which Genomic Health's breast cancer and colorectal cancer recurrence tests operate.
Genomic Health presented top-line results from the study at the Society for Urologic Oncology annual meeting last week and plans to release complete data at the American Society for Clinical Oncology's Genitourinary Cancer Symposium in February.
"We have reached an important milestone in our clinical development of a test for prostate cancer by narrowing down specific genes and pathways that predict prostate cancer aggressiveness," said Shak.
The 295 "significantly predictive" genes linked to prostate cancer recurrence represented a subset of 732 cancer-related and reference genes that the researchers initially explored in the study.
"The number of genes predicting clinical recurrence was well in excess of that expected by chance alone," the company said in a statement. Additionally, Genomic Health reported that a large portion of these 295 genes were "strongly associated" with additional endpoints, such as prostate-specific antigen recurrence (75 percent of genes); prostate cancer-specific survival (84 percent of genes); and upgrading/upstaging from biopsy to radical prostatectomy (68 percent of the genes).
Furthermore, the researchers found that increased expression of cytoskeleton genes, such as FLNA, and epithelia genes, such as KRT5, were signals of lower risk of recurrence. Meanwhile, the study results suggested that increased expression of extracellular matrix genes, such as COL3A1, may be associated with higher risk of recurrence.
"Using a standardized quantitative technique combined with rigorous central review of pathology and clinical data, this study clearly demonstrates a strong association between tumor gene expression and clinical recurrence," Eric Klein, chairman of the Glickman Urological and Kidney Institute at the Cleveland Clinic, said in a statement.
In Klein's view, if Genomic Health's test is successfully able to differentiate between "clinically indolent and aggressive disease," it could be a diagnostic tool for doctors to decide whether to keep monitoring a patient with localized prostate cancer, move ahead with prostatectomy or radiation therapy, or treat with adjuvant therapy after initial treatment.