SAN FRANCISCO—Few elderly men with localized prostate cancer will die from the malignancy after 10 years even in treatment is delayed, so active surveillance for these patients may be a reasonable option, according to researchers.
Grace Lu-Yao, PhD, MPH, of the Cancer Institute of New Jersey in New Brunswick, and her colleagues studied 9,018 men diagnosed with T1/T2 prostate cancer from 1992 to 2002 who did not receive initial local therapy or androgen deprivation within six months of diagnosis.
Of these men, 187 had low-grade malignancy, 7,544 had moderate-grade malignancy, and 1,287 had high-grade malignancy. The median age at cancer diagnosis was 77 years and the median follow-up was 94 months. The median time to any cancer therapy was 127 months. Of the 9,018 men, 5,879 were aged 75 years and older at diagnosis.
During the study period, 6,523 men (72%) died of competing causes of death or did not have
documented cancer complications that required surgery or radiation, the researchers reported here at the 2008 Genitourinary Cancers Symposium. The corresponding figures for men with low-, moderate-, and high-grade malignancy were 87%, 73%, and 65%, respectively. The overall 10-year prostate cancer-specific mortality was 5.3%; it was 6%, 3%, and 17% for patients with low-, moderate-, and high-grade cancer, respectively.
Weigh risks and benefits
“Patients need to weight the potential risks and benefits of various treatment options in making treatment decisions,” the investigators concluded.
Dr. Lu-Yao’s group noted that prostate cancer-specific mortality in their PSA era cohort was substantially lower than was found in studies conducted in patients diagnosed with the malignancy in the pre-PSA era.
Other recent studies have provided data suggesting that active surveillance may be an acceptable management strategy for selected patients with localized, low-risk prostate cancer. Some data, however, point to a survival benefit associated with immediate treatment compared with observation in men with localized prostate cancer, such as a study published in the Journal of the American Medical Association (2006;296:2683-2693).
The researchers compared two groups of men with localized low- and intermediate-risk prostate cancer: one underwent observation and the other received treatment with radical prostatectomy or radiation within six months of diagnosis. At the end of the 12-year study period, 37% of the observation group had died compared with 23.8% of the treatment group.
The treatment group had longer five- and 10-year survival than the observation group. Treatment was associated with a 31% reduced risk of death. The investigators found a treatment benefit in all subgroups, including older men (age 75-80 years at diagnosis).