Three dimensional conformal photon radiotherapy at a moderate dose level of 66 Gy for prostate carcinoma: early results.
BACKGROUND
The therapeutic outcome and toxicity of 3-D conformal photon external beam therapy of prostate cancer is well documented in the literature. Progress is still in work for optimization of treatment strategies by risk-adapted dose escalation studies to improve local tumor control without increase of radiation side effects.


METHODS
We present our experience of 291 patients treated between January 1994 and August 1997 with a 3-D planned four-field box technique and a central dose of 66 Gy. Biochemical response of patients with radiotherapy alone (group 1, n = 72 pts.) has been analyzed in detail. Acute radiation side effects are given for all patients (n = 291), late radiation side effects are given for patients treated between Jan 1994 and Jan 1996 with a median follow-up of 22 months (n = 115 pts.).


RESULTS
We have observed a biochemical response (nadir PSA < 1 after 12 months, < 2 after 6 months) for patients treated with radiotherapy alone without hormone manipulation in 67%. Incidence of late rectal and bladder morbidity (grade 2 and 3) was 9.4% and 4%, respectively.


CONCLUSIONS
Compared to other reports our results indicate a high rate of local tumor control (early biochemical response) and a low rate of late morbidity. Nevertheless, we will start a risk-adapted dose escalation study up to 74 Gy for unfavorable subgroups (G2-3, Gleason Score > 7, PSA > 10) to improve treatment outcome.
Wachter
S
S
Department of Radiotherapy and Radiobiology, University Hospital Vienna, Austria. stefan.wachter@akh-wien.ac.at
Gerstner
N
N
Goldner
G
G
Dieckmann
K
K
Colotto
A
A
Pötter
R
R
D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D009017:Morbidity; D009367:Neoplasm Staging; D017785:Photons / Q000009:adverse effects / Q000627:therapeutic use; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000453:epidemiology / Q000209:etiology; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000009:adverse effects; D012007:Rectum / Q000528:radiation effects; D001743:Urinary Bladder / Q000528:radiation effects
D017430:Prostate-Specific Antigen