Prostate cancer and PSA: Should your patient get screened?
Brendan Curti, M.D.
Medical director, Providence Genitourinary Oncology Research, Providence Biotherapy Program
Robert W. Franz Cancer Research Center in the Earle A. Chiles Research Institute
Oncologist, Providence Oncology and Hematology Care Clinic-Eastside
To screen or not to screen? For men concerned about their risk of prostate cancer, that is the question.
At least 18 different medical associations have made recommendations regarding the prostate-specific antigen, or PSA, test to screen for prostate cancer, yet there is little consensus among these expert panels. In the medical literature, you’ll find some studies pointing out benefits from PSA screening, and others suggesting that screening makes no difference.
As a physician who treats men with advanced prostate cancer, my own bias is that screening is valuable for select patients, particularly men between the ages of 50 and 70.
Over time, the numbers tell a story
As a marker for prostate cancer, PSA has its limitations. Both cancerous prostate cells and normal prostate cells produce PSA. While higher-than-normal levels of PSA in the blood could be an indication of prostate cancer they also can be a normal response to inflammation, infection, prostate enlargement or other benign factors.
To make matters more confusing, low levels of PSA do not necessarily suggest the absence of cancer. Up to 15 percent of men with normal PSA levels may have prostate cancer on biopsy; however, most of these cancers are not aggressive.
Despite these limitations, doctors still can glean important information from the PSA test by comparing results from year to year. A gradual rise in PSA is normal as a man ages and his prostate grows larger, but a significant rise in PSA from one year to the next could indicate an emerging cancer, and should be followed up with further testing.
The value of PSA increases when combined with a digital rectal exam. The two tests together can help catch more cancers than either screening method alone. Any prostate abnormality found on physical exam, particularly if accompanied by high PSA levels, should be followed up with a biopsy, which is the only way to confirm a diagnosis of prostate cancer.
Recent studies published in the New England Journal of Medicine and in the Journal of the American Medical Association show that, for men in otherwise good health, aggressive, up-front treatment yields better outcomes and extends life longer than watchful waiting or more conservative management. (As with screening, treatment strategies should be tailored to each patient’s detailed findings on exam and biopsy and overall medical health.)
Medical, surgical and radiation treatments for prostate cancer have made significant advances in recent years. For instance, a robotic surgery system used at Providence Portland and Providence St. Vincent medical centers can shorten hospital stays and speed recovery. Radiation technology for localized prostate cancer has progressed as well, and there is a long list of advances in medical treatment, especially for men with more advanced disease.
In addition to improvements in traditional treatments, research teams at Providence Cancer Center and throughout the country are discovering new avenues for treatment, such as immunotherapy and better ways to block testosterone, which is the main growth signal for prostate cancer cells.
Guidelines for screening
Most medical organizations agree that screening should be part of the conversation between patient and physician. Generally accepted guidelines suggest annual screenings for:
• Healthy men between the ages of 50 and 70
• African-Americans, who are at higher risk for prostate cancer, starting at age 45
• Men with a strong family history of prostate cancer, beginning at age 40
There is more controversy about the value of continued screening for men 70 and older. Determining whether to continue is a decision that each man should make with his doctor.
Screening may not be for every man, but early detection and treatment can make a significant and positive difference for many.
Clinical articles by Brendan Curti, M.D.
Ipilimumab a leap forward in melanoma treatment
Providence research advances immunotherapy for prostate cancer
Expert Q&A: Breakthroughs in prostate cancer research
Awards and recognition
Prostate Cancer Foundation Creativity Award