title: Influence of intensity-modulated radiotherapy on acute genitourinary and gastrointestinal toxicity in the treatment of localized prostate cancer.
abstract: The objective of this investigation is to compare acute genitourinary (GU) and gastrointestinal (GI) toxicity results of radiotherapy to localized fields delivered using intensity-modulated radiotherapy (IMRT) versus conventional radiotherapy (ConvRT). The records of 481 consecutive prostate cancer patients receiving RT to localized fields at a single institution were reviewed; 108 received IMRT and 373 received ConvRT. Acute GU and GI toxicity, as defined by the Radiation Therapy Oncology Group (RTOG) grading system, were compared using the chi-square test. Ordered logit regression analyses were performed using all major disease and treatment factors as covariates. Acute GU grade 0, 1, 2, 3, and 4 toxicity rates were 23%, 40%, 34%, 3%, and 0%, respectively, in the IMRT cohort and 31%, 37%, 30%, 1%, and 1%, respectively, in the ConvRT cohort -- these rates were not significantly different (p=0.118). Acute GI grade 0, 1, 2, 3, and 4 toxicity rates were 42%, 37%, 22%, 0%, and 0%, respectively, in the IMRT cohort and 33%, 32%, 35%, 0%, and 0%, respectively, in the ConvRT cohort--this lower toxicity in the IMRT group was significant (p=0.013). The regression analyses showed that only IMRT use (p=0.046) predicted reduction in acute GI toxicity but no factors correlated with acute GU toxicity rate. In conclusion, in our retrospective single-institution analysis, IMRT was not associated with reduction of acute GU toxicity but was associated with a reduction of acute GI toxicity over ConvRT in the treatment of prostate cancer to localized fields.
authors.affiliation: Dept. of Radiation and Cellular Oncology, University of Chicago Hospitals, 5758 S. Maryland Ave., MC 9006, Chicago, IL 60637, USA. jani@rover.uchicago.edu
authors.forename: Ashesh B
authors.initials: AB
authors.lastname: Jani
authors.forename: John
authors.initials: J
authors.lastname: Gratzle
authors.forename: David
authors.initials: D
authors.lastname: Correa
mesh_terms: D000368:Aged; D041981:Gastrointestinal Tract / Q000528:radiation effects*; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*; D016896:Treatment Outcome; D014566:Urogenital System / Q000528:radiation effects*