Multi-institutional Prospective Evaluation of Bowel Quality of Life After Prostate External Beam Radiation Therapy Identifies Patient and Treatment Factors Associated With Patient-Reported Outcomes: The PROSTQA Experience
- Department of Biostatistics, The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan (United States)
- Department of Urology, The University of Michigan Medical Center, Ann Arbor, Michigan (United States)
- Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, California (United States)
- Office for Survey Research, Michigan State University, East Lansing, Michigan (United States)
- Department of Radiation Oncology, The Massachusetts General Hospital, Boston, Massachusetts (United States)
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Boston, Massachusetts (United States)
- Department of Radiation Oncology, The Cleveland Clinic, Cleveland, Ohio (United States)
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
- Department of Urology, Emory University Medical Center, Atlanta, Georgia (United States)
- Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States)
Purpose: To evaluate patients treated with external beam radiation therapy as part of the multicenter Prostate Cancer Outcomes and Satisfaction with Treatment Quality Assessment (PROSTQA), to identify factors associated with posttreatment patient-reported bowel health-related quality of life (HRQOL). Methods and Materials: Pretreatment characteristics and treatment details among 292 men were evaluated using a general linear mixed model for their association with measured HRQOL by the Expanded Prostate Cancer Index Composite instrument through 2 years after enrollment. Results: Bowel HRQOL had a median score of 100 (interquartile range 91.7-100) pretreatment and 95.8 (interquartile range 83.3-100) at 2 years, representing new moderate/big problems in 11% for urgency, 7% for frequency, 4% for bloody stools, and 8% for an overall bowel problems. Baseline bowel score was the strongest predictor for all 2-year endpoints. In multivariable models, a volume of rectum ≥25% treated to 70 Gy (V70) yielded a clinically significant 9.3-point lower bowel score (95% confidence interval [CI] 16.8-1.7, P=.015) and predicted increased risks for moderate to big fecal incontinence (P=.0008). No other radiation therapy treatment-related variables influenced moderate to big changes in rectal HRQOL. However, on multivariate analyses V70 ≥25% was associated with increases in small, moderate, or big problems with the following: incontinence (3.9-fold; 95% CI 1.1-13.4, P=.03), rectal bleeding (3.6-fold; 95% CI 1.3-10.2, P=.018), and bowel urgency (2.9-fold; 95% CI 1.1-7.6, P=.026). Aspirin use correlated with a clinically significant 4.7-point lower bowel summary score (95% CI 9.0-0.4, P=.03) and an increase in small, moderate, or big problems with bloody stools (2.8-fold; 95% CI 1.2-6.4, P=.018). Intensity modulated radiation therapy was associated with higher radiation therapy doses to the prostate and lower doses to the rectum but did not independently correlate with bowel HRQOL. Conclusion: After contemporary dose-escalated external beam radiation therapy up to 11% of patients have newly identified moderate/big problems with bowel HRQOL 2 years after treatment. Bowel HRQOL is related to baseline function, rectal V70, and aspirin use. Finally, our findings validate the commonly utilized cut-point of rectal V70 ≥25% as having significant impact on patient-reported outcomes.
- OSTI ID:
- 22224510
- Journal Information:
- International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 3 Vol. 86; ISSN IOBPD3; ISSN 0360-3016
- Country of Publication:
- United States
- Language:
- English
Similar Records
Quality of Life After Whole Pelvic Versus Prostate-Only External Beam Radiotherapy for Prostate Cancer: A Matched-Pair Comparison
A Multi-institutional Clinical Trial of Rectal Dose Reduction via Injected Polyethylene-Glycol Hydrogel During Intensity Modulated Radiation Therapy for Prostate Cancer: Analysis of Dosimetric Outcomes