By: Fatema Elias, Senior Staff Editor

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Prostate cancer occurs when abnormal cells form in the tissues of the prostate gland. It often develops in men over the age of 50, and the numbers of estimated new cases and of deaths from prostate cancer in the United States in 2013 are 238,590 and 29,720, respectively.¹

Screening is a form of primary prevention for prostate cancer. Finding abnormal tissue as soon as it is formed allows for easier and more variable treatment options. The American Cancer Society (ACS) recommends that men discuss with their doctors whether or not they choose to be screened for prostate cancer. High risk groups include 50-year-old men at average risk of prostate cancer who are expected to live 10 more years, 40-year-old men at high risk of prostate cancer, African American men who have a first-degree relative with prostate cancer before age 65, or 40-year-old men at higher risk due to having more than one first-degree relative with prostate cancer before age 65.² Patients are currently screened using the Prostate Specific Antigen blood test, the Digital Rectal Examination and the Gleason score.² Once the results of prostate cancer screening come back positive, further testing, such as biopsy, is done to evaluate patient specific treatment.

Although screenings can detect the presence of cancer, there has been no way to detect how aggressive a cancer is until now. For example, it may be a slow growing tumor that could not be of any harm, or a tumor that needs priority attention due to its aggressiveness.³ Without a test to detect the prognosis of this cancer, men may take medication or undergo treatments that could have otherwise been avoided. Overdiagnosis and overtreatment are common and result in treatment-related detriment.⁴

A new prostate cancer screening, the Prolaris^® test, is a genetic test that can distinguish between aggressive and gradual cancers.⁵ This test utilizes an expression signature that determines the relationship between the genes that are involved in cell cycle progression (CCP) and prostate cancer. The expression signature is made of 31 cell cycle progression genes and 15 housekeeper genes.⁶ The test measures the level of expression of the 31 genes that are involved in proliferation of cancer cells and therefore detects how quickly the cells are dividing and spreading. Two people with the same PSA level and Gleason score may not receive the same result from the Prolaris^® screening test, and therefore would require different treatment regimens than otherwise thought. ⁵A low score tells the physician that they can likely delay treatment if necessary, whereas a high score indicates that doctors should talk to their patients about aggressive management. Prostate cancer, like all cancers, is distressing, and so being able to predict the likelihood of it spreading to other parts of the body is important. With this new test, more men will be appropriately diagnosed, fewer men will receive unnecessary treatment and its resulting side effects, and those men who need immediate attention due to rapid growth will receive it.

The research that led to the development of this test included five retrospective studies. The Prolaris^® score was tested at diagnosis in two patient population cohorts (n=337 and n=349), after radical prostatectomy in two cohorts (n=366 and n= 413), and after external beam radiation therapy in the last cohort (n=141).⁶ The five cohort studies were assessed through the CCP signature.⁶ The retrospective studies shows the Prolaris^® test proved to be significant in being a strong predictor for prognosis of prostate cancer. The Prolaris^® score ultimately demonstrates statistical significance when testing biochemical recurrence (BCR) and multivariate analysis with p=0.0017 and p=0.034 respectively.⁶ The study demonstrates the clinical significance in multiple patient populations in diverse clinical settings.

This new screening test may spare men from needing operations. Though the impact of the novel test developed is being studied prospectively in clinical utility studies, the data seems promising.⁷ Professor Dan Berney of the Queen Mary University of London says, “We need to validate it and we’re not there yet, but it is the strongest test we’ve had so far.”⁸ If this test can allow us to determine how far the prostate cancer has progressed, one of the biggest challenges in treating this cancer will be tackled—determining whether surgery is necessary to remove the prostate completely. Currently, the decision to remove the prostate is based on an examination of a tumor sample under the microscope. Prolairs^® will also allow doctors to effectively monitor patients and provide appropriate medication therapy based on the patient’s needs.

Prolaris^®offers meaningful prognosis data for patients diagnosed with prostate cancer. This novel screening test provides doctors with an effective way to manage their patients’ conditions.

SOURCES:

1. Prostate cancer. National Cancer Institute Website. http://www.cancer.gov/cancertopics/types/prostate Updated March 1, 2014. Accessed April 30, 2014.
2. American Cancer Society recommendations for prostate cancer early detection. American Cancer Society Website. http://www.cancer.org/cancer/prostatecancer/moreinformation/prostatecancerearlydetection/prostate-cancer-early-detection-acs-recommendations Published August 28, 2013. Updated February 25, 2014. April 30, 2014..
3. ‘False positive’ concern over prostate cancer test. BBC News Health. http://news.bbc.co.uk/2/hi/health/8448147.stm Published January 11, 2010. Accessed April 30, 2014.
4. Ilic D, Neuberger MM, Djulbegovic M, Dahm P. Screening for prostate cancer. Cochrane Database of Systematic Reviews 2013, Issue 1. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0012972/ Published January 21, 2013. April 30, 2014.
5. The prolaris test: move forward with confidence. The Prolaris Test Website. http://www.prolaris.com/information-for-patients/about-prolaris/ Updated March 1, 2014. Accesed April 30, 2014.
6. Berney D, Brawer M, Cooperberg M, Swanson G, Freeland S. CCP Score: A novel genetic test for prostate cancer. 2013 NCRI Cancer Conference Website. http://conference.ncri.org.uk/abstracts/2013/abstracts/LB4.htm Updated February 17, 2014. Accessed April 30, 2014.
7. Prostate cancer; myriad’s prolaris significantly modifies treatment decisions for prostate cancer patients. Medical Devices & Surgical Technology Week. 2014;179. http://search.proquest.com/docview/1494416822?accountid=14068. Published Fenruary 16, 2014. Accessed April 30, 2014.
8. Gallagher J. Prostate cancer aggression test ‘may avoid needless ops’. BBC News Health. http://www.bbc.com/news/health-24805626 Published November 4, 2013. Accessed April 30, 2014.

[pubmed_related keyword1=”prostate” keyword2=”cancer” keyword3=”men”]

Published by Rho Chi Post