Outcomes following iodine-125 brachytherapy in patients with Gleason 7, intermediate risk prostate cancer: a population-based cohort study.
OBJECTIVE
To evaluate outcome in patients with Gleason 7 prostate cancer treated with iodine-125 brachytherapy at the British Columbia Cancer Agency.


METHODS
Between 20th July 1998 and 7th February 2006, 1500 patients underwent I-125 prostate brachytherapy without supplemental external beam radiation therapy. Of these, 439 had Gleason 7 disease; 362 had Gleason 3+4 and 77 had 4+3 disease. Generally, patients received 6 months of androgen suppression. We compared biochemical no evidence of disease (bNED) between patients with Gleason ≤ 6 and Gleason 7 and between Gleason 3+4 and 4+3 using the Phoenix definition of biochemical recurrence.


RESULTS
Median follow-up was 60 months. Estimated 5 year bNED was 97% for patients with Gleason score ≤ 6 and 94% for patients with Gleason 7 disease (p=0.037). Estimated bNED was 95% and 94% for 3+4 and 4+3, respectively (p=0.791). There was no difference in bNED between implants achieving D90 ≥ versus<the median value (150.5 Gy) or ≥ versus<140 Gy.


CONCLUSIONS
I-125 brachytherapy with 6 months of ADT demonstrates excellent bNED rates in Gleason 7 disease. We found no evidence of a difference between patients with Gleason 3+4 versus 4+3 disease.
Department of Radiation Oncology, BC Cancer Agency, Vancouver, Canada.
Christopher
C
Herbert
W James
WJ
Morris
Mira
M
Keyes
Jeremy
J
Hamm
Vincent
V
Lapointe
Michael
M
McKenzie
Thomas
T
Pickles
Ingrid
I
Spadinger
D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D015331:Cohort Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D016896:Treatment Outcome
D007457:Iodine Radioisotopes