Phase II trial of hypofractionated image-guided intensity-modulated radiotherapy for localized prostate adenocarcinoma.
OBJECTIVE
To assess in a prospective trial the feasibility and late toxicity of hypofractionated radiotherapy (RT) for prostate cancer.


METHODS
Eligible patients had clinical stage T1c-2cNXM0 disease. They received 60 Gy in 20 fractions over 4 weeks with intensity-modulated radiotherapy including daily on-line image guidance with intraprostatic fiducial markers.


RESULTS
Between June 2001 and March 2004, 92 patients were treated with hypofractionated RT. The cohort had a median prostate-specific antigen value of 7.06 ng/mL. The majority had Gleason grade 5-6 (38%) or 7 (59%) disease, and 82 patients had T1c-T2a clinical staging. Overall, 29 patients had low-risk, 56 intermediate-risk, and 7 high-risk disease. Severe acute toxicity (Grade 3-4) was rare, occurring in only 1 patient. Median follow-up was 38 months. According to the Phoenix definition for biochemical failure, the rate of biochemical control at 14 months was 97%. According to the previous American Society for Therapeutic Radiology and Oncology definition, biochemical control at 3 years was 76%. The incidence of late toxicity was low, with no severe (Grade > or =3) toxicity at the most recent assessment.


CONCLUSIONS
Hypofractionated RT using 60 Gy in 20 fractions over 4 weeks with image guidance is feasible and is associated with low rates of late bladder and rectal toxicity. At early follow-up, biochemical outcome is comparable to that reported for conventionally fractionated controls. The findings are being tested in an ongoing, multicenter, Phase III trial.
Martin
Jarad M
JM
Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON, Canada.
Rosewall
Tara
T
Bayley
Andrew
A
Bristow
Robert
R
Chung
Peter
P
Crook
Juanita
J
Gospodarowicz
Mary
M
McLean
Michael
M
Ménard
Cynthia
C
Milosevic
Michael
M
Warde
Padraig
P
Catton
Charles
C
D000230:Adenocarcinoma / Q000097:blood / Q000473:pathology / Q000532:radiotherapy* / Q000556:secondary; D000368:Aged; D001706:Biopsy; D019583:Dose Fractionation, Radiation; D005240:Feasibility Studies; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D016879:Salvage Therapy / Q000379:methods
D017430:Prostate-Specific Antigen