LOS ANGELES--"Prostate cancer is a disease of options,"
Douglas Keyser, MD, said at the American Society for Therapeutic
Radiology and Oncology (ASTRO) meeting. And individual treatment
decisions are difficult to make because of the lack of randomized
studies and head-to-head comparisons between radiation therapy
Now, new data from the Departments of Radiation Oncology and Urology,
at the Cleveland Clinic Foundation, show that in early prostate
cancer, results with radiation therapy and surgery are nearly
identical, Dr. Keyser said at a scientific session on genitourinary
The investigators reviewed charts from 1,467 consecutive prostate
cancer patients treated between 1987 and 1996 at the Cleveland
Clinic, looking for those with early prostate cancer (pretreatment
PSAs of 10 ng/mL or less and clinical stage T1 or T2 disease)
who had received either radiation therapy or surgery with no adjuvant
or neoadjuvant therapy.
Of the resulting 607 patients, 253 had been treated with radiation
therapy and 354 with radical prostatectomy (one third of whom
had positive surgical margins). "The radiation patients were
significantly older, but overall the pretreatment characteristics
of the two groups were very similar," Dr. Keyser said.
The study endpoint was biochemical relapse-free survival, which
was defined as a rise in PSA above 0.2 after prostatectomy, and
a rise of greater than 1.0 from the nadir after radiation therapy.
The data were also analyzed using a newer definition of biochemical
failure--three consecutive rising PSA levels above the nadir.
"Overall biochemical relapse-free survival was very good
for the entire group (75% at 5 years) as we would expect for these
patients," Dr. Keyser said. And the 5-year results were the
same for radiotherapy (75%) and prostatectomy (76%). These results
did not vary in the reanalysis based on the newer definition of
An analysis of outcome based on pretreatment factors showed that
patients with Gleason scores of 7 or greater "seemed to fare
better with radiation therapy, perhaps due to the higher margin-positive
rate in these patients," he noted.