Age plays too big a role in prostate cancer treatment decisions

The scientists found that men above age 75 with high-risk prostate cancer often are under-treated through hormone therapy or watchful waiting alone in lieu of more aggressive treatments such as surgery and radiation therapies. Instead, say the researchers, old age should not be viewed as a barrier to treatments that could lead to potential cures.

“There is a disconnect between risk and treatment decisions among older men,” said senior investigator Matthew R. Cooperberg, MD, MPH. “Patient age is strongly influencing treatment decisions, so we sought to understand whether age plays a role in risk of the disease and survival. We found that under-treatment of older-men with high-risk disease might in part explain higher rates of cancer mortality in this group. There is also pervasive over-treatment of low-risk disease in this age group. Overall, treatment needs to be selected more based on disease risk and less based on chronologic age.”

The study is published by the “Journal of Clinical Oncology,” and is available online at http://jco.ascopubs.org/content/early/2010/12/02/JCO.2010.30.2075.full.pdf+html?sid=fe9ef2e4-1379-4e7b-ab6c-c33796334de4

Prostate cancer is the most common form of cancer in men and the second most common cause of cancer death after lung cancer. This year, an estimated 217,730 men will be diagnosed with the disease, and 32,050 men will die from it, reports the American Cancer Society. Moreover, prostate cancer is the most common malignancy among older men: 64 percent of new cases in the United States this year were diagnosed in men older than 65, and 23 percent in men above 75.

Yet most studies delving into optimal treatment options focus on men younger than 75. The new UCSF study is among the first to explore the relationship between age, disease risk and survival among prostate cancer patients.

The researchers studied men in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) database, a longitudinal, observational disease registry of men with prostate cancer who were recruited from urology practices throughout the United States. At the time of the study, the database contained information on 13,805 patients.

The scientists found that older patients are more likely to have high-risk prostate cancer at the point of diagnosis, and less likely to receive potentially curative local therapy. Yet when older, high-risk men received more aggressive treatment, they had a 46 percent lower death rate compared with patients treated more conservatively with hormonal therapy or watchful waiting.

The finding, the researchers say, suggests that underuse of aggressive therapy may in part explain the higher death rates of older men with the disease.

“Age does not independently predict prostate cancer survival,” said Peter R. Carroll, MD, MPH, chair of the UCSF Department of Urology and co-leader of the prostate program at the UCSF Helen Diller Family Comprehensive Cancer Center. He is a co-author of the paper. “Our findings support making treatment decisions on the basis of disease risk and life expectancy rather than on chronologic age.”

The researchers note that the U.S. Preventive Services Task Force specifically recommends against screening men age 75 or older, but that position is based on studies on younger men, and furthermore does not account for health status or other diseases that the patients may have which would affect life expectancy.

“Older men with high-risk disease frequently die of prostate cancer and under-treatment might be a factor in their deaths,” said Cooperberg, a prostate cancer specialist in the UCSF Department of Urology and the Helen Diller cancer center. “The notion of age as a primary determinant should be reconsidered. Patients with aggressive local disease should be offered a chance of aggressive therapy that might cure them regardless of their age.”

Traditionally, Cooperberg said, physicians have feared the risks of surgery on their older patients. But for older patients with localized, high-risk disease – and a life expectancy of more than 10 years – the researchers recommend that surgical treatment and radiation be considered.

“Surgery and radiation risks do go up with age, but it may be that we are focusing too much on risk than on benefit,” said Cooperberg. “We need a better balance between risk and benefit.”

Seth K. Bechis, a UCSF medical student now in residency at Massachusetts General Hospital, is the lead author of the paper.

Carroll and Cooperberg report receiving honoraria unrelated to the study from Takeda Pharmaceuticals, and Cooperberg additionally from Abbott Laboratories. Abbott supports CaPSURE in part, and additional funding is provided through several federal grants.

UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care.

Follow UCSF on Twitter @ucsf/@ucsfscience