Four PCa studies presented at the 2015 AUA annual meeting in New Orleans shed some light, with researchers emphasizing the need to optimize screening and to improve treatment selection in older men.
Questions about the optimal approach to prostate cancer screening and treatment for the disease continue to have urologists and other practitioners searching for answers. Four studies presented at the 2015 AUA annual meeting in New Orleans shed some light, with researchers emphasizing the need to optimize screening and to improve treatment selection in older men.
Stacy Loeb, MD, MSc, of New York University School of Medicine, New York, who moderated a press briefing about the research, spoke with Urology Times in a one-on-one interview. She shared her insight on the study findings and what they mean for clinicians.
Stacy Loeb, MD, MScThe first study, presented by Matthew Cooperberg, MD, MPH, of the University of California, San Francisco, examined data from CaPSURE, a community-based prostate cancer registry of 47 clinical sites across the U.S. (since 1995). Researchers compared prostate cancer-specific deaths across all major primary treatment alternatives, including local treatment, surgery, brachytherapy, external beam radiation, and primary hormonal therapy.
“We don’t know exactly what is the best kind of treatment,” Dr. Loeb said. “In his data set, he [Dr. Cooperberg] showed that for all comers, prostatectomy had the lowest rate of prostate cancer death. But if you just look in the low-risk group of patients, there was no difference between any of the treatments or active surveillance/watchful waiting.”
The study found active surveillance was a viable option for most men with low-risk prostate cancer, and aggressive multimodal treatment, including surgery, was effective for men with high-risk disease.
“It appears that surgery is a great option as a first treatment for high-risk disease and, at least in this non-randomized data, reduces the risk of prostate cancer death. For low-risk disease, active surveillance is safe and should be encouraged,” said Dr. Loeb.
Barry Stein, MD, of Albany Stratton Veterans Affairs Medical Center in Albany, NY, examined patterns of prostate cancer diagnosis by age. Using records of 545 patients diagnosed at the VA Center, the researchers categorized patients by age group and found the oldest group (aged 70-99 years) had the highest percentage of high-risk prostate cancer (41.1% had a disease stage >T2b, 41.1% had a Gleason grade of 8-10, and 73.4% had a PSA >20 ng/mL), while the youngest group (aged 40-49 years ) had the highest percentage of low-risk disease. The mortality rate from prostate cancer was as high as that from other causes.
Recommended - A new castration-resistant prostate cancer entity?
The data suggest that prostate cancer may not be innocuous in older adults and that men over the age of 70 years were just as likely to die of prostate cancer as they were from other causes.
Dr. Stein “showed that older men are more likely to be diagnosed with aggressive prostate cancer, and a greater proportion of them died from prostate cancer compared to younger men. This agrees with other studies suggesting that older men are more likely to be diagnosed with high-risk disease,” said Dr. Loeb.
In a similar study led by Par Stattin, MD, PhD, of Umeå University and including colleagues from Sweden and New York, researchers looked at patients in their 70s diagnosed with high-risk prostate cancer. Dr. Loeb presented the study’s findings.
The study demonstrated that otherwise healthy men in their 70s with high-risk, non-metastatic prostate cancer (HRnMPCa) are less likely than younger men with similar life expectancies to receive curative treatment. The nationwide, population-based study evaluated 19,190 men with HRnMPCa who were diagnosed in Sweden from 2001 to 2012, to assess how age and comorbidities affect treatment.
Interesting - How the economy predicts PCa diagnosis, management
The proportion of men under 70 years of age who received curative treatment for HRnMPCa varied depending on life expectancy, but this was not the case for men in their 70s. Only 10% of men ages 75-80 years with no comorbidities received curative treatment despite a 52% 10-year survival probability, compared to half of men younger than 70 years of age with a similar life expectancy.
“Professor Stattin’s study showed that many of them were not receiving curative treatment for their prostate cancer. This may be an unintended consequence of all of the debate about overtreatment,” Dr. Loeb said. “We now may be actually under-treating healthy men in the 70s who have high-risk disease. Professor Stattin’s presentation showed that healthy men in their 70s with high-risk prostate cancer are most likely to die of prostate cancer. Twenty percent of them die from prostate cancer at 10 years without treatment, and that was a higher cause of death than cardiovascular disease or any other disease.
“Why are so few of them actually getting curative treatment for a disease that will kill them? This highlights a need for better estimation of life expectancy so that we can make appropriate treatment decisions.”
Researchers from the University of Kansas Medical Center in Kansas City, including first author Philip Fontenot, MD, examined whether men who develop incurable prostate cancer may not be failures of screening, but may have never undergone appropriate testing in the first place. The research evaluated current trends of standard screening (first PSA test prior to age 55 years). Using records of 93 men diagnosed with prostate cancer with metastatic disease or who died from the disease between 2008 and 2014, patients were stratified into four groups by disease presentation.
Of men treated for localized prostate cancer who later had metastasis or death from the disease, only four (15.4 %) had standard screening before age 55. Most of the men had metastatic disease at presentation. Only 9% of those with symptomatic metastatic prostate cancer had undergone standard screening prior to diagnosis, while 28% of men with asymptomatic metastatic prostate cancer had undergone standard screening.
Recommended - Prognostic factors identified in patients taking PCa Tx
The researchers looked backwards at men in their registry with metastatic prostate cancer to see how much screening they had and whether metastic disease could have been prevented, Dr. Loeb explained.
“They found that only 13% of the men with metastatic disease had a PSA test before the age of 55,” she said. “This is just not enough. This is too few and too late. We do need to alert young men that a baseline PSA measurement at a young age is the best way to assess the risk of developing life-threatening prostate cancer.
“This study is unique by looking directly at the men with metastatic disease to see their patterns of PSA testing, and it agrees with other studies looking forward. There is a nice model from Dr. Etzioni’s group [at Fred Hutchinson Cancer Center] projecting that if we discontinue screening as suggested by the U.S. Preventive Services Task Force, metastatic cases will double by 2025.”
Together, the four studies offer some important take-away messages about prostate cancer screening and treatment, according to Dr. Loeb.
You might like - PCa castration study fuels surgery vs. GnRHA debate
“We do need to be more careful about selection for prostate cancer screening, and screening needs to be focused on young, healthy men who should be offered a baseline test to assess their risk of life-threatening prostate cancer and to find those life-threatening patients in time for a cure,” said Dr. Loeb.
“On the flip side, older men are more likely to be diagnosed with high-risk disease, and under-treatment of those men could cause an undo burden of prostate cancer death. So on the treatment side, we should be better about estimating life expectancy to help our patients make good decisions about treatment.
“We are finally moving away from a one-size-fits-all approach to prostate cancer,” she added. “In the past, everyone got PSA tests once a year… and the vast majority of men diagnosed with prostate cancer were prompted directly to treatment. There was a lot less attention paid to personalized risk assessment.
“We are now moving into the era of personalized medicine where we can do a better job of selecting patients for both screening and treatment, taking into account multiple factors including their general health status to help them make a better choice for them as an individual.”