Seeds Beat Out Watchful Waiting
Men With Prostate Cancer Less Likely to Die if They Get Radiation Seed Implants
Oct. 31, 2007 (Los Angeles) -- Older men with prostate cancer who chose
treatment with radiation seed implant therapy or surgery cut their risk of
dying of the disease by more than half, compared with those who opt for close
observation, researchers report.
"This is the first time it’s been shown that seed implants are better
than watchful waiting in terms of survival," researcher Ester H. Zhou, MD,
PhD, of Case Western Reserve University School of Medicine in Cleveland, tells
The study involved about 11,000 men 65 and older with newly diagnosed cancer
that was confined to the prostate or that had only spread to nearby
tissues. About 30% chose a strategy of "watchful waiting," which
involves close monitoring for tumor growth.
Over the next seven years, those who got seed implants within six months of
being diagnosed were about 55% less likely to die of the cancer than those who
chose watchful waiting. Surgery to remove the prostate cut the risk of dying of
the disease by up to 75%.
The findings were presented at the American Society for Therapeutic
Radiology and Oncology’s (ASTRO) annual meeting.
To Treat or Not to Treat
There has been a long debate in the medical community about the value of
treatment to destroy cancer cells vs. watchful waiting, also known as active
Because prostate cancer often grows so slowly it may never become
life-threatening, many of these men, particularly older men, may die of causes
other than the cancer. But in some men, the cancer will spread beyond the
prostate without treatment. Then it may no longer be curable.
Treatment usually involves surgical removal of the prostate, external beam
radiation therapy, or radiation seed implants.
In external beam radiation therapy, a beam of high-dose radiation is aimed
at the prostate to kill cancer cells.
In radiation seed implant therapy, or brachytherapy, surgeons implant tiny
radioactive seeds into the prostate gland. The seeds deliver high-dose
radiation directly to the prostate for a predetermined length of time.
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.
Watchful Waiting Still Good Option
Anthony Zietman, MD, a prostate cancer specialist at Harvard Medical School
and a spokesman for ASTRO, says that the men who weren’t treated in the study
may have had other conditions that prevented them from getting active
"These men may have been sicker to begin with, so you can’t really
conclude that active treatment is better," he tells WebMD.
"Active surveillance is especially important for men with other
conditions such as heart disease that could kill them within a few years
anyway," Zietman says.
For otherwise healthy men, active surveillance is also "a perfectly
acceptable option," he adds.
"If you watch men closely and the cancer proves to be a tiger, you’ll
know in the first few years and you can still treat them to cure before it’s
"If it’s a pussycat, the PSA will never go up, a biopsy a year or two
later will show no changes, and you can avoid treatment. That’s a beautiful
thing," Zietman says.
Phillip M. Devlin, MD, a cancer specialist at Harvard Medical School and a
spokesman for ASTRO, says that he thinks any man with prostate cancer who is in
otherwise good health should opt for active treatment, regardless of age.
Active treatment is the only way to ensure a cure, Devlin tells WebMD.