Intensity-Modulated Radiotherapy Reduces Gastrointestinal Toxicity in Patients Treated With Androgen Deprivation Therapy for Prostate Cancer

Journal Article · Wed Jun 01 00:00:00 EDT 2011 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2010.02.040· OSTI ID:21491757

Sharma, Navesh K ^[1]; Tianyu, Li ^[2]; Chen, David Y ^[3]; Pollack, Alan ^[4]; Horwitz, Eric M ^[1]

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1. Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)
2. Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, PA (United States)
3. Department of Urologic Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)
4. Department of Radiation Oncology, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL (United States)

Purpose: Androgen deprivation therapy (AD) has been shown to increase late Grade 2 or greater rectal toxicity when used concurrently with three-dimensional conformal radiotherapy (3D-CRT). Intensity-modulated radiotherapy (IMRT) has the potential to reduce toxicity by limiting the radiation dose received by the bowel and bladder. The present study compared the genitourinary and gastrointestinal (GI) toxicity in men treated with 3D-CRT+AD vs. IMRT+AD. Methods and Materials: Between July 1992 and July 2004, 293 men underwent 3D-CRT (n = 170) or IMRT (n = 123) with concurrent AD (<6 months, n = 123; {>=}6 months, n = 170). The median radiation dose was 76 Gy for 3D-CRT (International Commission on Radiation Units and Measurements) and 76 Gy for IMRT (95% to the planning target volume). Toxicity was assessed by a patient symptom questionnaire that was completed at each visit and recorded using a Fox Chase Modified Late Effects Normal Tissue Task radiation morbidity scale. Results: The mean follow-up was 86 months (standard deviation, 29.3) for the 3D-CRT group and 40 months (standard deviation, 9.7) for the IMRT group. Acute GI toxicity (odds ratio, 4; 95% confidence interval, 1.6-11.7; p = .005) was significantly greater with 3D-CRT than with IMRT and was independent of the AD duration (i.e., <6 vs. {>=}6 months). The interval to the development of late GI toxicity was significantly longer in the IMRT group. The 5-year Kaplan-Meier estimate for Grade 2 or greater GI toxicity was 20% for 3D-CRT and 8% for IMRT (p = .01). On multivariate analysis, Grade 2 or greater late GI toxicity (hazard ratio, 2.1; 95% confidence interval, 1.1-4.3; p = .04) was more prevalent in the 3D-CRT patients. Conclusion: Compared with 3D-CRT, IMRT significantly decreased the acute and late GI toxicity in patients treated with AD.

• OSTI ID: 21491757
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 80, Issue 2; Other Information: DOI: 10.1016/j.ijrobp.2010.02.040; PII: S0360-3016(10)00332-9; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ANDROGENS
BLADDER
NEOPLASMS
PROSTATE
RADIATION DOSES
RADIOTHERAPY
RECTUM
THREE-DIMENSIONAL CALCULATIONS
TOXICITY
ANDROSTANES
BODY
DIGESTIVE SYSTEM
DISEASES
DOSES
GASTROINTESTINAL TRACT
GLANDS
HORMONES
INTESTINES
LARGE INTESTINE
MALE GENITALS
MEDICINE
NUCLEAR MEDICINE
ORGANIC COMPOUNDS
ORGANS
RADIOLOGY
STEROID HORMONES
STEROIDS
THERAPY
URINARY TRACT