Prostate cancer is the most common non-skin cancer and the second leading cause of cancer-related death in men in the United States, according to the National Cancer Institute.
Prostate cancer incidence rates in the U.S. began to increase dramatically in the late 1980s with the widespread use of the prostate-specific antigen (PSA) test to detect prostate cancer. Since the early 1990s, prostate cancer incidence has been declining. The NCI reported mortality rates for prostate cancer also have declined since the mid-1990s thanks to early detection. Today, governmental agencies and other groups are questioning the necessity of annual PSA screenings, once touted as a breakthrough in the world of men’s health.
“The American Academy of Family Physicians always said that prostate cancer screening wasn’t effective because they questioned the effectiveness of treatment,” explained David Penson, MD, MPH, chair in Urologic Oncology and professor of Urologic Surgery and Medicine at Vanderbilt University Medical Center. “When studies showed treatments were effective in many patients, the AAFP then noted that a lot of men were being over treated for prostate cancer.” Penson said the flip side of the PSA screening controversy is being driven by some urologists who want annual population-wide screenings in all men age 50 and over.
AUA Guidelines
The latest guidelines from the American Urological Association recommend against PSA screening in men under age 40 — a population with a low prevalence of clinically detectable prostate cancer. The AUA also discourages routine screening in men between ages 40-54 at average risk.
Higher risk men include those with a positive family history of the disease or of African American race. Guidelines don’t make recommendations in this group because there is little evidence for or against screening in these men, Penson explained. He cautioned that American trials were predominately in white men – the group at lowest risk of prostate cancer.
“The flip side is that patients at high risk for prostate cancer are not in the same category,” Penson said. “PSA screenings in African American men or those with a strong family history are a very different discussion.”
According to the AUA, the greatest benefit of screening appears to be in men ages 55 to 69 years at average risk. Guidelines state: “The Panel recognizes that the decision to undergo PSA screening involves weighing the benefits of preventing prostate cancer mortality in 1 man for every 1,000 men screened over a decade against the known potential harms associated with screening and treatment. For this reason, the Panel strongly recommends shared decision-making for men age 55 to 69 years that are considering PSA screening and proceeding based on a man's values and preferences.”
A Personal Choice
“It’s important to recognize that this is not a recommendation for population-wide screening, but rather a recommendation for a balanced discussion between patient and provider with the patient ultimately making a personal decision whether or not to screen based on his own preference,” said Penson.
He suggests patients work with their doctor to come to the best shared decision. “When I talk to a patient I say, ‘Look here’s this test, and it’s not a perfect test and a lot of things can come out of it. The process of diagnosing cancer can be associated with side effects. On the other hand, studies show there’s a benefit to doing this, so you have to make a personal decision.’”
He also reminds patients that they can always stop the process – an elevated PSA level doesn’t have to necessitate a biopsy or mean cancer. In fact, an enlarged prostate is the most common cause of an elevated PSA and is a benign condition. “There are a lot of places where the process can be stopped, and most people would rather know than not know,” he said.
Low-risk Prostate Cancer
One criticism of screening - quite valid a decade ago - was that it resulted in over treatment. That’s because many prostate cancers are slow growing, and men over 65 are often at higher risk of dying from heart disease or other forms of cancer before ever becoming symptomatic. Men who undergo prostatectomy are at risk for side effects including urinary incontinence and erectile dysfunction.
“What we see now is increased use of active surveillance, which is very appropriate, and effectively is acknowledging that not all prostate cancers need to be aggressively treated,” said Penson. In fact, most are monitored with repeated PSAs and biopsies. Active surveillance is now the preferred plan of choice of urologists for patients with low-risk prostate cancer, which comprise nearly 40-50 percent of cases.
“It’s amazing how well men do on active surveillance,” Penson said. “We’re learning how best to follow the cancer and run different tests with the prostate tissue, which gives us new information on the aggressiveness of tumors.”
Men with low-risk prostate cancer can go years with little change, although roughly a third opt for treatment out of worry. Often times the decision is spurred on by fearful family members who hear the “C” word and demand aggressive therapy. There’s even a movement afoot to change the name of low-grade prostate cancer altogether. Regardless, Penson believes education will evolve and the general public will soon realize low-risk prostate cancer is a different ballgame from its less common, more aggressive counterpart.
“We learned very early on that PSA screenings turn the clock back,” he said of early detection. The lead-time associated with PSA screening is 10 years or more, so providers are catching it a decade earlier than they would have with no test.
“The bottom line is that we need to recognize that both extreme sides of the argument are probably wrong,” Penson said of the PSA screening controversy. “Like everything else the reality is that there’s a happy medium. There’s a benefit to screening but you need to do it in a way that minimizes harm.”
Prostate Cancer Treatment
While robotic-assisted prostatectomy and radiation are still preferred treatment methods for cancer, medical therapies are evolving quickly. Considered a death sentence a decade ago, metastatic castrate-resistant prostate cancer now can be treated with six approved medications shown to improve survival, and therapies are being used earlier. “In the coming decade, I expect to see an explosion in medical therapies including pills, shots and immunotherapy, capable of changing the paradigm of treatment,” Penson said.
RELATED LINKS:
AUA Prostate Cancer Detection Guidelines
