Can Prostate Cancer Be
Detected Early?
By Raul A. Alvarez Arrazola, MD
Prostate cancer can often be found early by testing the amount of prostate-specific antigen (PSA) in your blood. Prostate cancer may also be found when your doctor does a digital rectal examination (DRE). Because your prostate gland lies just in front of your rectum, the doctor can feel if there are any nodules or areas of abnormal hardness in your prostate.
There are potential problems with the current screening methods. Neither the PSA test nor the DRE is 100% accurate.
ACS Recommendations for the Early Detection of Prostate Cancer
The American Cancer Society believes that health care professionals should offer the prostate-specific antigen (PSA) blood test and digital rectal examination (DRE) yearly, beginning at age 50, to men who have at least a 10-year life expectancy.
Men at high risk, such as African Americans and men who have a first-degree relative (father, brother, or son) diagnosed with prostate cancer at an early age (younger than age 65), should begin testing at age 45.
Men at even higher risk (because they have several first-degree relatives who had prostate cancer at an early age) could begin testing at age 40. Depending on the results of this initial test, further testing might not be needed until age 45.
Men should actively participate in the decision by learning about prostate cancer and the pros and cons of early detection and treatment of prostate cancer.
Prostate-Specific Antigen (PSA) Blood Test
Prostate-specific antigen (PSA) is a substance made by the normal prostate gland. Although PSA is mostly found in semen, a small amount is also present in the blood. Most men have levels under 4 nanograms per milliliter (ng/mL) of blood.
Your PSA level can also be affected by other factors: non-cancerous enlargement of the prostate, prostatitis.
Ejaculation can cause a temporary increase in blood PSA levels, so some doctors will suggest that men abstain from ejaculation for 2 days before testing.
Some medicines may affect blood PSA levels - finasteride (Proscar or Propecia) or dutasteride (Avodart) –
Herbal preparations may also affect blood PSA levels. Herbal mixtures that are dietary supplements marketed “for prostate health” may affect PSA level, they could potentially mask an elevated PSA level, which is why it is important to let your doctor know if you are taking any type of supplement. Saw palmetto (an herb used by some men to treat BPH) does not seem to interfere with the measurement of PSA.
Use of the PSA Blood Test After Prostate Cancer Diagnosis
The PSA test can be used together with clinical examination results and tumor grade to help decide which tests are needed for further evaluation.
After surgery or radiation treatment, the PSA level can be monitored to help determine if the treatment were successful.
Digital Rectal Exam (DRE)
During this exam, a doctor inserts a gloved, lubricated finger into the rectum to feel for any irregular or firm area that might be a cancer. The prostate gland is located just in front of the rectum, and most cancers begin in the back part of the gland that can be reached by a rectal exam. While it is uncomfortable, the exam causes no pain and only takes a short time.
American Cancer Society guidelines recommend that when prostate cancer screening is done, both the DRE and PSA blood test should be used.
Transrectal Ultrasound (TRUS)
When a small probe is placed in the rectum, sound waves enter the prostate and create echoes that are picked up by the probe. A computer turns the pattern of echoes into a picture.
TRUS is usually not recommended as a routine test by itself to detect prostate cancer because it doesn’t often spot early cancer. Instead, it is most commonly used during a prostate biopsy (described in the next section). TRUS is used to guide the biopsy needle into exactly the right area of the prostate.
TRUS is useful in other situations as well. It can be used to measure the size of the prostate gland, which can help determine the PSA density and may also affect which treatment options a man has. It is also used as a guide during some forms of treatment, such as cryosurgery.
Raul Alfredo Alvarez Arrazola, MD, completed his radiology residence at Hospital San Jose – Monterrey Tech. At present, he works in the Radiology Department AMERIMED Hospitals. Puerto Vallarta.
If you have any questions or would like to schedule an appointment, please call (322) 226-2080 or email: ralvarez@amerimed-hospitals.com
