Prostate-specific antigen (PSA) is a protein that is produced by the prostate of adult men. A simple blood test is able to measure the small amounts of PSA that circulates through a man’s body. The level of PSA measure in the blood, loosely correlates with the size of the prostate. Bigger prostates produce more PSA, while smaller prostates produce less. Most prostate cancers also produce PSA, which has lead to using the PSA as a screening tool for prostate cancer.
Prostate cancer is the most common type of cancer in men, and the second leading cause of cancer-specific death in men. Medicine has been searching for a way to prevent deaths from prostate cancer. For the last 20 years, conventional wisdom has said the PSA screening and early detection is our best method.
In October of 2011, the US Preventative Services Task Force, the governmental body that reviews medical research and develops practice guideline, reviewed the current literature on using the PSA to screen for prostate cancer with the goal of answering four basic questions.
- Does PSA-Based Screening Decrease Prostate Cancer–Specific or All-Cause Mortality?
- What Are the Harms of PSA-Based Screening for Prostate Cancer?
- What Are the Benefits of Treatment of Early-Stage or Screening-Detected Prostate Cancer?
- What Are the Harms of Treatment of Early-Stage or Screening-Detected Prostate Cancer?
In a best case scenario, the taskforce estimated that 48 men diagnosed with prostate cancer through PSA screening would have to be treated to prevent a single death from prostate cancer, a success rate of just 4%. Depending on the treatment, radiation or surgery, 7-16 of those men would suffer lasting erectile dysfunction. 10 of those men would suffer urinary incontinence. Even more concerning, 1 in 200 men, undergoing surgery will die from surgical complications. The report did not factor in the estimated 3 billion dollars in annual expense that PSA screening costs.
The details of the report are somewhat dense, but the conclusion was clear. The harm to the many, does not justify the benefit to the few. Conventional treatments for prostate cancers detected by PSA screening do not offer a benefit to the vast majority of men.
These results, ultimately, lead the taskforce to recommend against screening men for prostate cancer using PSA. That recommendation ignores the many factors, independent from PSA, that can predict a man’s risk for prostate cancer. Prostate cancer screening should incorporate all aspects of a man’s health: his age, race, physical exam findings, family history, medication and supplement usage, and the PSA.
The findings of the taskforce, also reminds us that conventional treatments for early stage prostate cancer carry a significant risk, without a corresponding benefit.
Republished with permission from Green Tea and Melatonin.
