PHILADELPHIASignificant benefit can be achieved from long-term
androgen suppression following neoadjuvant hormonal cytoreduction and
radiotherapy in locally advanced prostate cancer.
This finding from a phase III RTOG study was reported at ASCO by
Gerald Hanks, MD, of Fox Chase Cancer Center.
According to Dr. Hanks, local progression, biochemical progression,
deaths due to prostate cancer, and 5-year survival were all
significantly improved in patients who received 24 months of
goserelin (Zoladex) after initial goserelin, flutamide (Eulexin), and
radiation therapy, compared to patients who did not receive the
This was a study of long-term total androgen suppression
following neoadjuvant hormonal cytoreduction, Dr. Hanks
explained. Arm 1 was goserelin and flutamide for 2 months before and
roughly 2 months during radiation therapy. Arm 2 was goserelin and
flutamide for 2 months before and 2 months during radiation therapy,
then goserelin alone for 24 months.
Designated RTOG Protocol 92-02, this study was a prospective
randomized trial of androgen suppression and external beam radiation
in patients with locally advanced prostate cancer (T2C-T4) with PSA
less than 150 ng/mL.
This was a remarkable study, Dr. Hanks said. It
opened in June of 1992 and closed less than 3 years later, in April
of 1995, with a total accrual of 1,557 patients. Median
follow-up was 4.9 years.
Local progression was 12% in short-term vs 6% in long-term androgen
suppression. Biochemical progression by 5 years was 47% vs 22%.
Deaths due to prostate cancer at 5 years were 7.2% vs 4.3%.
Although there is no difference yet in overall survival, with
every cancer progression indicator including rate of metastasis and
cause-specific death being different, overall survival will change
with more time, Hanks predicted.
Subset analysis showed a long-term survival advantage with long-term
androgen suppression in patients with Gleason 810 tumors. The
difference was 69% vs 80% at 5 years (P = .01).
There was a significant increase in RTOG grade 3-4 bowel
complications in the long-term androgen suppression group, 42 vs 26.
This study supports the continued use and study of long-term
androgen deprivation in patients with poorly differentiated or
locally advanced prostate cancers, Dr. Hanks commented.
He said that long-term androgen deprivation is superior to short-term
in patients with locally advanced prostate cancer. It is
particularly important in patients with Gleason 810
tumors, he said. All of these patients should have an
opportunity to be treated with this combined modality.
This treatment now becomes the standard against which innovative
treatments for this locally advanced disease should be compared in
randomized trials, he concluded.