PROSTATE CANCER: CAN A SIMPLE BLOOD DRAW AFFECT MY PROGNOSIS?

What is PSA?
Prostate-specific antigen (PSA) is a protein produced by both cancerous (malignant) and noncancerous (benign) prostate tissue.  PSA helps liquefy the semen and enters the bloodstream at variable rates depending on the health of the prostate.  Because PSA is present in both benign and cancerous prostate cells, it’s not specific to only prostate cancer.  However, cancer cells usually make more PSA than do benign cells, causing PSA to rise early in the course of prostate cancer.

The complicating issue is that conditions other than prostate cancer also can cause PSA levels to rise, including benign enlargement of the prostate (BPH), inflammation of the prostate (prostatitis) and other less common conditions.  Some prostate cancers, particularly those of an aggressive nature, may not produce much PSA, so the digital rectal examination (DRE) remains an important part of evaluating the prostate.

Besides the number itself, other factors that go into interpreting PSA scores include your age, the size of your prostate and how quickly your PSA levels are changing.  There can be much complexity in these relating factors, so it is important that a physician experienced in interpreting PSAs evaluate your situation so that you can avoid unnecessary or inappropriate testing and treatment.

• Age– As you get older, your risk of prostate cancer increases. After age 50, your chance of having prostate cancer increases substantially.  About 70% of all diagnosed prostate cancers are found in men age 65 years or older.  The option to have PSA testing begins at age 50 (40 if you have risk factors)
• Race or ethnicity– For reasons that aren’t well understood, black men have a higher risk of prostate cancer and fatalities from the disease are subsequently higher.
• Family history– If a close family member, your father, or brother has prostate cancer, your risk of the disease is greater than that of the average American man.
• Diet– Studies have shown a high-fat diet and obesity may increase your risk of prostate cancer

Before you get a PSA test, be sure to discuss if you are using finasteride for hair loss, (Propecia), or finasteride for benign prostatic hypertrophy (Proscar).  Studies show that finasteride can significantly decrease your measured PSA levels.

Dr. Bellman notes that if you are using one of these products, your measured PSA levels can be increased up to double to reflect a more accurate result.  Other medications that contain components of male or female hormones also can change your PSA value and knowing about all of the medicines and supplements you are using will help for an accurate reading.