PCA3 – the new gene-based urine test specific for Prostate Cancer

This article is an excerpt from Dr. Anhorn's full article titled: "Dual Approach to Integrative Cancer Care - Step 1: Improving your outcome."

 

This excerpt discusses the controversies and pitfalls of the PSA test, and presents the latest advancements in prostate cancer diagnosis and care -- in particular, the new gene-based urine test specific for prostate cancer (PCA3 test).

 

Proper diagnosis: Death of the PSA test?

In medicine, in order to get the best outcome, you need the correct diagnosis. In Canada, one of the main diagnostic tests used to detect prostate cancer is a blood test called the prostate specific antigen (PSA). This type of test is called a screening test. Screening tests are designed to allow for early diagnosis in order to reduce the number of deaths from a disease. There is an organization called the U.S. Preventative Task Force that assesses each of the screening methods used in medicine and creates a recommendation based on the strength of the evidence and the balance of benefits and risks of a preventive service. When the Task Force assessed prostate screening in 2012 they officially recommended that “no one be screened with a PSA test because it doesn't actually show a survival benefit.” After going through the research, they found that the reduction in prostate cancer deaths from PSA screening is at most very small. A large U.S. study showed no benefit from screening. A large European study that found the highest reported benefit suggests that no more than 1 in 1,000 men avoids death from prostate cancer because of screening. Other studies found no benefit at all.

 

The Task Force found that PSA screening also has important potential harms. The PSA screening test has an 80% false positive rate -- meaning 80% of the elevated PSA tests are suggestive of prostate cancer, but are not actually cancer. In fact, anything that affects the gland (infection, prostatitis, sex, cycling, benign prostate hyperplasia (BPH), etc) can elevate the PSA level. When the doctor receives this elevated PSA score, most patients get sent for an immediate biopsy. Therefore, 75-80% of the patients receiving the biopsy did not actually need the biopsy done. Not only does this experience cause worry and anxiety, but roughly one third of men receiving the biopsy experience unpleasant side effects, and there are also some concerns of the biopsy potentially spreading the cancer.

 

Since there are an increased number of biopsies conducted, there are an increased number of early prostate cancers found. Almost all of these men (90%) end up undergoing treatment with surgery, radiation, or hormone therapy. However, many of these men did not actually need treatment because their cancer would never have grown or cause any health problems during their lifetime, even without treatment. This type of cancer is called “indolent” cancer. Indolent cancer is often stereotyped as a form where “the patient will live 20 years and probably pass away from something else.” According to the 2010 data from the American Cancer Society, it takes 14 unnecessary prostate cancer treatments to save 3 men from dying of it. In other words, 82% of prostate cancer treatments are unnecessary.

 

The unfortunate part of overtreatment is that the men receiving these unnecessary prostate cancer treatments may now suffer from lifelong damage, such as:

  • Erectile dysfunction (impotence) from surgery, radiation therapy, or hormone therapy in 75% of cases;
  • Urinary incontinence (leakage of urine) from radiation therapy or surgery in 54% of cases;
  • Problems with bowel control from radiation therapy lasting 5 years post-radiation; and
  • High rates of depression from these complications.
  • As you can see there is a snowball effect: the inaccuracy of the PSA test leads to an increase number of unnecessary biopsies; the increased number of biopsies results in the overdiagnosis of prostate cancer; the overdiagnosis leads to overtreatment; and the overtreatment leaves many of these indolent cancer patients with lifelong complications.

 

Therefore, new testing procedures are needed to ensure proper diagnosis and to prevent these unnecessary downstream procedures.

 

Proper diagnosis: PCA3 - the new gene-based urine test specific for prostate cancer

In late 2011, there was a new test that was approved by the FDA. The PCA3 test is a gene-based test that is performed on a urine sample. PCA3 stands for prostate cancer gene 3, a gene that is involved in development of prostate cancer.

 

Unlike PSA, the PCA3 result is not falsely elevated when a man suffers from a disease that increases the size of the prostate such as benign prostatic hyperplasia (BPH) or prostatitis. PCA3 is specific to prostate cancer cells. Therefore, it gives very useful information that can be used in combination with the PSA, in deciding if a biopsy is really needed.

 

The men that would most benefit from this new PCA3 testing are:

  • men who have an abnormal PSA level, with or without a negative biopsy result.
  • men who have already had a negative biopsy result.
  • men who have a high cancer risk, or a family history of prostate cancer, even if you have a low PSA level.
  • men who have already had treatment (e.g. surgery or radiation) for prostate cancer but want to monitor their health.
  • If you have an elevated PSA or other suspicious clinical findings (e.g. a suspicious DRE) and are facing a biopsy decision.
  • If you have had a negative tumour-free biopsy but suspicion for prostate cancer remains.
  • If you have a family history of prostate cancer.
  • If you have a positive biopsy, i.e. cancer cells have been found in the biopsy, and want to know more about the aggressiveness of the cancer.
  • If you have early, non-aggressive prostate cancer and are followed by active surveillance/monitoring and want to know if the cancer is progressing. 

 

The Moncton Naturopathic Medical Clinic is proud to announce that we now have access to this new PCA3 testing for our patients. To find out more information about the testing please call the clinic at 506-382-1329.

 

 

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Dual Approach to Integrative Cancer Care -- Step 2: Preventing Cancer Re-Occurrence

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Intravenous Alpha Lipoic Acid (ALA) in Cancer Care

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