3D interstitial HDR brachytherapy combined with 3D external beam radiotherapy and androgen deprivation for prostate cancer. Preliminary results.
BACKGROUND
Evaluation of feasibility, tolerance and efficiency for a new 3D interstitial HDR brachytherapy technique combined with 3D external beam radiotherapy and androgen deprivation for prostate cancer.


METHODS
Between January 1997 and August 1998 we treated 35 patients with stage cT1-3 N0 M0 prostate cancer. Thirty-two patients with a follow-up of 12 to 28 months (median: 18 months) were evaluated. After ultrasound-guided transrectal implantation of 4 non-parallel needles, CT based 3D brachytherapy treatment planning ("Offenbach system") was performed. All patients received 4 fractions brachytherapy using a fractional dose of 5 or 7 Gy. Time between each fraction was 14 days. After brachytherapy 3D external irradiation followed up to 39.6 or 45.0 Gy. All patients received androgen deprivation, starting 2 to 19 months before brachytherapy, ending 3 months after 3D external radiotherapy.


RESULTS
Posttreatment PSA levels dropped to < 1.5 ng/ml in 29/32 patients (91%). In 25 patients PSA levels were < 0.5 ng/ml, in 4 patients 0.5 to 1.5 ng/ml. In 2 patients we noted biochemical relapse. Transrectal implantation was very well tolerated. Grade 3 acute urinary toxicity occurred in 1 patient. We noted no Grade 2 or higher acute gastrointestinal toxicity. One patient developed a Grade 3 late urinary toxicity. No patient showed late gastrointestinal side effects. All 140 dose-volume histograms for 3D HDR brachytherapy were analyzed.


CONCLUSIONS
The new 3D HDR brachytherapy technique, combined with 3D external irradiation and androgen deprivation, is a feasible, so far well-tolerated and effective treatment in the short-time follow-up of median 18 months.
Martin
T
T
Strahlenklinik, Städtische Kliniken Offenbach, Germany. Doc-Martin@T-online.de
Hey-Koch
S
S
Strassmann
G
G
Kolotas
C
C
Baltas
D
D
Rogge
B
B
Röddiger
S
S
Vogt
H G
HG
Heyd
R
R
Dannenberg
T
T
Kurek
R
R
Tunn
U
U
Zamboglou
N
N
D000230:Adenocarcinoma / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy* / Q000532:radiotherapy*; D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D001706:Biopsy; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D003131:Combined Modality Therapy; D005240:Feasibility Studies; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010315:Particle Accelerators; D017785:Photons / Q000009:adverse effects / Q000627:therapeutic use*; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood / Q000528:radiation effects; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy* / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D013997:Time Factors
D000726:Androgen Antagonists; D017430:Prostate-Specific Antigen