Feb. 13, 2008 -- Most older men with early-stage prostate cancer can safely choose close observation instead of active treatment and all of its potential side effects, a new study suggests.
Researchers examined data on more than 9,000 older men with localized prostate cancer who were not initially treated for the disease. Ten years later, about four-fifths were alive without any complications of their disease or had died of other causes.
The findings support a strategy of "watchful waiting" -- close monitoring for signs of tumor growth -- in many older men, says researcher Grace Lu-Yao, PhD, a cancer epidemiologist at The Cancer Institute of New Jersey and an associate professor at the University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School and School of Public Health.
"Currently there is no effective tool to determine who needs treatment," Lu-Yao tells WebMD. "Our data will help patients to know what will happen if they don't have treatment."
The Watchful-Waiting Debate
Because prostate cancer often grows so slowly it may never become life-threatening, many of these men, particularly older men, may die of other causes before the cancer causes problems. But in some men, the cancer will spread beyond the prostate without treatment. Then it's no longer curable.
As a result, there has been a long-running debate in the medical community about the value of treatment to destroy cancer cells vs. watchful waiting, also known as active surveillance.
Treatment usually involves surgical removal of the prostate or radiation therapy. Impotence, urinary incontinence, and bowel problems are all potential side effects of the most widely used treatments for prostate cancer.
Watchful waiting consists of close monitoring with periodic digital rectal exams, biopsies, and PSA (prostate-specific antigen) blood tests. Rising PSA levels can be a sign of prostate cancer spread in men with early cancer.
Lu-Yao says the new study is one of the first to describe the natural history of prostate cancer during the current era when PSA testing is common. This is important because PSA tests can help detect cancer six to 13 years earlier than traditional diagnostic methods, she says.
In contrast to older studies, the current trial also included a large number of elderly patients. More than 5,000 participants were over age 75, she says.
"This is the group of patients most likely to benefit from active surveillance but for whom little is known due to lack of data," Lu-Yao says.
The findings will be reported this week at the Genitourinary Cancers Symposium (GSC) in San Francisco.
Prostate Cancer: Patients Overtreated?
The researchers examined data on 9,018 men from the NCI's Surveillance, Epidemiology and End Results (SEER) database who had been diagnosed with stage I or II prostate cancer between 1992 and 2002; the men did not receive surgery, radiation, or hormonal therapy within six months of diagnosis.
They were 66 to 104 years old when diagnosed.
As expected, men with less aggressive disease fared better than those with high-grade cancers. After 10 years, 3% to 7% of those with low- or moderate-grade disease had died of prostate cancer, compared with 23% of men with high-grade cancers.
The higher the grade of prostate cancer, the more likely it will grow and spread rapidly.
GCS spokesman Howard M. Sandler, MD, a radiation oncologist at the University of Michigan, says most prostate cancer specialists think that men with the cancer are overtreated.
"This study provides additional data to support the role of active surveillance, especially in patients with low-grade disease," Sandler tells WebMD.
Prostate cancer is the second most common cancer among men. It is diagnosed in more than 218,000 men and claims more than 27,000 lives each year.
GCS is co-sponsored by the American Society for Clinical Oncology and two other leading cancer care organizations.