(125)I monotherapy using D90 implant doses of 180 Gy or greater.
OBJECTIVE
The purpose of this study was to characterize the oncologic results and toxicity profile of patients treated with (125)I implants using the dose delivered to 90% of the gland from the dose-volume histogram (D90) of greater than 144 Gy.


METHODS
From June 1995 to Feb 2005, a total of 643 patients were treated with (125)I monotherapy for T1-T2 prostate cancer with a D90 of 180 Gy or greater (median, 197 Gy; range, 180-267 Gy). Implantations were performed using a real-time ultrasound-guided seed-placement method and intraoperative dosimetry to optimize target coverage and homogeneity by using modified peripheral loading. We analyzed biochemical disease-free survival (bDFS) of 435 patients who had a minimum 2-year prostate-specific antigen follow-up (median follow-up, 6.7 years; range, 2.0-11.1 years).


RESULTS
Five-year bDFS rates for the entire cohort using the American Society for Therapeutic Radiology and Oncology and Phoenix definitions were 96.9% and 96.5%, respectively. Using the Phoenix definition, 5-year bDFS rates were 97.3% for low-risk patients and 92.8% for intermediate/high-risk patients. The positive biopsy rate was 4.1%. The freedom rate from Grade 2 or higher rectal bleeding at 5 years was 88.5%. Acute urinary retention occurred in 10.7%, more commonly in patients with high pretreatment International Prostate Symptom Scores (p < 0.01). In patients who were potent before treatment, 73.4% remained potent at 5 years after implantation.


CONCLUSIONS
Patients with a minimum D90 of 180 Gy had outstanding local control based on prostate-specific antigen control and biopsy data. Toxicity profiles, particularly for long-term urinary and sexual function, were excellent and showed that D90 doses of 180 Gy or greater performed using the technique described were feasible and tolerable.
Kao
Johnny
J
Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY 10029, USA.
Stone
Nelson N
NN
Lavaf
Amir
A
Dumane
Vishruta
V
Cesaretti
Jamie A
JA
Stock
Richard G
RG
D001706:Biopsy; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D018572:Disease-Free Survival; D006471:Gastrointestinal Hemorrhage; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D011788:Quality of Life; D011879:Radiotherapy Dosage; D012044:Regression Analysis; D018084:Ultrasonography, Interventional
D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen