Comparing measures of acute bowel toxicity in patients with prostate cancer treated with external beam radiation therapy.
OBJECTIVE
This study strives to compare early measures of bowel toxicity in patients with prostate cancer receiving definitive or adjuvant 3D conformal external beam radiation therapy and concurrent daily endorectal application of amifostine.


METHODS
Eighteen patients were enrolled in the clinical study with a median follow-up of 12 months. Prescription doses ranged from 66 Gy to 76 Gy with a daily fractionation of 2 Gy. Acute bowel toxicity was measured at baseline, at Weeks 5 and 7 of radiotherapy, and at 1 and 3 months after the completion of therapy. Measures of acute bowel toxicity included the Radiation Therapy Oncology Group (RTOG) acute radiation morbidity scoring criteria, Expanded Prostate Cancer Index Composite (EPIC) self-assessment questionnaires, and proctoscopic examinations.


RESULTS
The mean EPIC bowel scores changed significantly through the course of therapy and follow-up (p < 0.0001), with a progressive decrease in scores at Weeks 5 and 7 of treatment, a partial recovery at 3 months, and a correlation to the gold standard RTOG grade (p = 0.004). Proctoscopic toxicity scores were low, did not vary over time, and did not correlate with either EPIC or RTOG scores.


CONCLUSIONS
The EPIC questionnaire measurements are most sensitive to changes in acute bowel toxicity through a course of radiotherapy and correlate with RTOG acute toxicity scores. Endoscopic examination of the rectal mucosa at the end and immediate follow-up of a course of therapy does not seem to be informative or reproducible between observers in the acute setting.
Muanza
Thierry M
TM
Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Albert
Paul S
PS
Smith
Sharon
S
Godette
Denise
D
Crouse
Nancy Sears
NS
Cooley-Zgela
Theresa
T
Sciuto
Linda
L
Camphausen
Kevin
K
Coleman
C Norman
CN
Ménard
Cynthia
C
D000368:Aged; D004999:Amifostine / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D006801:Humans; D008297:Male; D008875:Middle Aged; D011351:Proctoscopy; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011788:Quality of Life; D011832:Radiation Injuries / Q000473:pathology*; D011837:Radiation-Protective Agents / Q000627:therapeutic use*; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal; D012007:Rectum / Q000528:radiation effects*; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires
D011837:Radiation-Protective Agents; D004999:Amifostine