Prostate Cancer Screening
Prostate cancer is one of the most common types of cancer in men, affecting the gland located under the bladder and in front of the rectum. Once malignant cells develop in the prostate, they multiply much more quickly than normal cells. Because prostate cancer can metastasize and become life-threatening, prostate cancer screening, designed to detect the disease at its earliest, most treatable stages, is important.
The Prostate Cancer Screening Procedure
There are two types of prostate cancer screening: a digital rectal examination and a prostate-specific antigen (PSA) blood test.
Digital Rectal Examination
The digital rectal examination is normally performed as part of a comprehensive physical examination during which the doctor inserts a gloved finger in the rectum to feel for any malformations or growths on the prostate gland. In order to be thorough, the doctor usually presses on the abdomen or pelvic area during this test.
Prostate-Specific Antigen or PSA Blood Test
The PSA test determines whether the individual has elevated levels of PSA in his blood. While PSA is a protein produced by normal cells as well as by cancerous ones, malignant cells typically produce more. Although men whose PSA level if over 4.0 nanograms per milliliter have been considered likely to have prostate cancer, recent studies show more variability, according to age, medical conditions, and even race and ethnicity.
It is important to note that PSA levels vary among individuals and can be increased by factors other than a malignancy. These factors include:
- Prostatitis
- Benign prostate hyperplasia or BPH (enlarged prostrate)
- Recent ejaculation
- Certain medical procedures, such as a prostate biopsy
- Certain medications, especially those prescribed for BPH
There is some controversy surrounding who should undergo the PSA screening. While the Center for Disease Control (CDC) recommends prostate screening only for men who have symptoms, the American Urological Association and the American Cancer Society recommend testing for men at elevated risk for developing prostate cancer, determined by factors such as age and family history of the disease. Organizations and physicians recommending PSA tests typically advise them for patients between the ages of 40 and 75 or for those with a family member who has had the disease.
Pros and Cons of Prostate Cancer Screening
While PSA screening can help to detect prostate cancer at earlier, more treatable stages, some prostate cancers are slow-growing and may never spread beyond the gland itself. In addition, PSA screening in not foolproof and may, under certain circumstances, yield false positive, or false negative, results. Because the treatment for prostate cancer can have serious side effects, such as impotence, urinary incontinence, or bowel dysfunction, many men are reluctant to undergo treatment that may or may not be necessary. Nonetheless, when prostate cancer is detected at an early stage, it is more likely to require less aggressive treatment with fewer side effects.
For some men, having a PSA screening with negative results provides peace of mind; for others, it leaves nagging doubts. Similarly, for some men, a PSA with positive results provides the conviction that prompt intervention will treat the disease effectively; for others, it creates confusion about which course of action to pursue.
Generally speaking, good results of a digital rectal exam, coupled with a normal PSA test, provide reassurance that it is unlikely the patient has prostate cancer. In the end, an informed decision has to be made by the patient in consultation with his physician.