Leonard G. Gomella, MD
The mortality rate from prostate cancer has declined significantly in the past few decades; however, there is much debate over how much PSA screening contributed to that decline. At the 2013 IPCC®, Leonard G. Gomella, MD, discussed his view that PSA screening, while not solely responsible for the reduction, is a critical component of prostate cancer management and should continue to be used with the appropriate patients.
“We have seen that the mortality [from prostate cancer] since the 1990s has continued to go down. And, in fact, if you look at the interval from about 1991 and you move it forward to about 2010- 2011, you’ll see almost a 50% decline in mortality [Figure
],” said Gomella, professor and chairman of the Department of Urology, and director of Clinical Affairs at the Jefferson Kimmel Cancer Center, Thomas Jefferson University Hospital in Philadelphia, Pennsylvania. “We are starting to see metastatic cancer go away, and PSA has led to stage migration—earlier and more treatable cancers, and we’ve seen the survival rate go up dramatically, so PSA screening is doing something good.”
Gomella stressed that screening alone did not produce the mortality decline. Rather, the synergistic effect from combining screening with treatment has improved outcomes. “[Screening is] one of the pieces of the puzzle that is improving the mortality from prostate cancer. It’s not all about screening—there are treatment effects [as well].”
What Does the Literature Show?
Gomella’s support for screening is rooted in clinical studies that have examined PSA testing. While initial trial results have varied, Gomella said the longer you follow-up and the closer you examine even the negative trials, the support is there for PSA screening. Of the three largest trials, the European Randomized Study of Screening for Prostate Cancer (ERSPC; N Engl J Med
. 2009;360:1320-1328) and the Göteborg trial (Lancet Oncol
. 2010;11:725-732) showed that PSA screening reduced prostate cancer mortality rates.
Figure. The PSA Dilemma
According to Leonard G. Gomella, MD, PSA screening is part of a group of factors including better therapy, earlier use of hormones, changes in death assignment, lifestyle changes, and medication use (statins/COX-2 inhibitors), that has led to a reduction in the overall prostate cancer mortality rate. However, the US Preventive Services Task Force has recommended against using PSA screening in any asymptomatic male.
Source: Gomella LG. Screening for prostate cancer: the PSA controversy. Presented at: 6th Annual Interdisciplinary Prostate Cancer Congress; March 16, 2013; New York, NY.
The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial (N Engl J Med
. 2009;360:1310- 1319) did not demonstrate a reduction in mortality; however, “In post-hoc analysis [of the PLCO data], it showed that if a man had more than one PSA test done, that he had a 25% reduction in his risk of prostate cancer death.” There was also contamination in the PLCO, as many men in the control group had PSA screening done outside of the trial. Additionally, Gomella said that a reanalysis of the PLCO data showed that if you “looked at men who had comorbidities and took them out, the study was positive.”
Gomella also noted that with screening studies, long-term follow-up is critical to demonstrating the true benefit of PSA testing. The data show that “as time goes on, the benefit of screening becomes greater and greater,” he said. For example, with the 11-year follow-up of the ERSPC (N Engl J Med
. 2012;366:981-990), the number of men who needed to be screened to prevent one prostate cancer death dropped from 1440 to 1055. Additionally, the number of men who needed to be treated to prevent one death dropped from 48 to 37.
Gomella said the bottom line with the clinical trial evidence is that screening is effective; however, the data do not support general population screening. To avoid overtreatment, screening should be targeted to specific individuals, according to Gomella. “[Screening]…makes sense in certain populations—those at high risk for the disease, those at high risk for death or morbidity from the disease, and those in good health [few comorbidities and a life expectancy of at least 10-15 years].”
Is PSA Screening in Jeopardy?
Gomella’s staunch defense of screening came amid concern from him and many of his colleagues that the use of PSA testing may be in jeopardy.