Toxicity analysis of postoperative image-guided intensity-modulated radiotherapy for prostate cancer.
OBJECTIVE
To report on the acute and late gastrointestinal (GI) and genitourinary (GU) toxicity associated with a unique technique of image-guided radiotherapy (IGRT) in patients undergoing postprostatectomy irradiation.


METHODS
Fifty patients were treated with intensity-modulated radiation therapy (IMRT) after radical prostatectomy. Daily image guidance was performed to localize the prostate bed using kilovoltage imaging or cone-beam computed tomography. The median prescription dose was 68 Gy (range, 62-68 Gy). Toxicity was graded every 3 to 6 months according to the Common Terminology Criteria for Adverse Events version 3.0.


RESULTS
The median follow-up was 24 months (range, 13-38 months). Grade 2 acute GI and GU events occurred in 4 patients (8%) and 7 patients (14%), respectively. No Grade 3 or higher acute GI or GU toxicities were observed. Late Grade 2 GI and GU events occurred in 1 patient (2%) and 8 patients (16%), respectively. Only a single (2%) Grade 3 or higher late toxicity was observed.


CONCLUSIONS
Image-guided IMRT in the postprostatectomy setting is associated with a low frequency of acute and late GI/GU toxicity. These results compare more favorably to radiotherapy techniques that do not use in-room image-guidance, suggesting that daily prostate bed localization may reduce the incidence of adverse events in patients undergoing postprostatectomy irradiation.
Nath
Sameer K
SK
Department of Radiation Oncology, Rebecca and John Moores Comprehensive Cancer Center, University of California -San Diego, La Jolla, USA.
Sandhu
Ajay P
AP
Rose
Brent S
BS
Simpson
Daniel R
DR
Nobiensky
Polly D
PD
Wang
Jia-Zhu
JZ
Millard
Fred
F
Kane
Christopher J
CJ
Parsons
J Kellogg
JK
Mundt
Arno J
AJ
D000368:Aged; D054893:Cone-Beam Computed Tomography; D005500:Follow-Up Studies; D041981:Gastrointestinal Tract / Q000528:radiation effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011184:Postoperative Period; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D011832:Radiation Injuries / Q000473:pathology*; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods; D016879:Salvage Therapy / Q000379:methods; D012720:Severity of Illness Index; D014566:Urogenital System / Q000528:radiation effects*