External beam radiation therapy (EBRT) dose escalation has been tested in multiple prospective trials. However, the impact on patient reported outcomes (PROs) associated with higher doses of EBRT remain poorly understood. We sought to assess the differences in PROs between men treated with a dose of 70.2 Gy versus 79.2 Gy of EBRT for prostate cancer.
The phase 3 clinical trial RTOG 0126 randomized 1532 patients with prostate cancer between March 2002 and August 2008 to 79.2 Gy over 44 fractions versus 70.2 Gy over 39 fractions. Eligible patients participated in the PRO data collection. PROs completed included the International Index of Erectile Function Questionnaire (IIEF), Functional Alterations due to Changes in Elimination (FACE), and the Spitzer Quality of Life Index (SQLI). The timepoints for the IIEF were collected pre-entry and at 6, 12, and 24 months. The FACE and SQLI were collected pre-entry and at 3, 6, 12, 18, and 24 months. The impact of EBRT dose to normal structures (penile bulb, rectum, and bladder) on PROs was also examined. Mixed effects models were used to analyze trends across time.
In total, 1144 patients completed baseline IIEF forms and of these, 56%, 64%, and 61% completed the IIEF at 6, 12, and 24 months, respectively; 1123 patients completed the FACE score at baseline and 50%, 61%, 73%, 61%, and 65% completed all 15 items for the FACE metric at timepoints of 3, 6, 12, 18, and 24 months, respectively. Erectile dysfunction at 12 months based on the single question was not significantly different between arms (38.1% for the standard dose radiation therapy arm vs 49.7% for the dose escalated radiation therapy arm; P = .051). Treatment arm (70.2 vs 79.2) had no significant impact on any PRO metrics measured across all collected domains. Comprehensive dosimetric analyses are presented and reveal multiple significant differences to regional organs at risk.
Compliance with PRO data collection was lower than anticipated in this phase 3 trial. Examining the available data, dose escalated EBRT did not appear to be associated with any detriment to PROs across numerous prospectively collected domains. These data, notwithstanding limitations, add to our understanding of the implications of EBRT dose escalation in prostate cancer. Furthermore, these results illustrate challenges associated with PRO data collection.
International journal of radiation oncology, biology, physics. 2022 Jan 01 [Epub]
William A Hall, Snehal Deshmukh, Deborah W Bruner, Jeff M Michalski, James A Purdy, Walter Bosch, Jean-Paul Bahary, Maltibehn P Patel, Matthew B Parliament, Michael I Lock, Harold Y Lau, Luis Souhami, Scot A Fisher, Young Kwok, Michael J Seider, Eric Vigneault, Seth A Rosenthal, Gary S Gustafson, Hiram A Gay, Stephanie L Pugh, Howard M Sandler, Benjamin Movsas
Froedtert and the Medical College of Wisconsin, Milwaukee, Wisconsin. Electronic address: ., NRG Oncology Statistics and Data Management Center, American College of Radiology, Philadelphia, Pennsylvania., Emory University, Atlanta, Georgia., Washington University School of Medicine, St. Louis, Missouri., University of California, Atlanata, Georgia., Centre Hospitalier de l'Universite de Montreal, Montreal, Quebec., Juravinski Cancer Centre at Hamilton Health Sciences, Hamilton, Ontario, Canada., Cross Cancer Institute, Edmonton, Alberta, Canada., London Regional Cancer Program, London, Ontario, Canada., Tom Baker Cancer Centre, Calgary, Alberta, Canada., McGill University, Montreal, Quebec., Thomas Jefferson University Hospital, Philadelphia, Pennsylvania., University of Maryland/Greenebaum Cancer Center, Baltimore, Maryland., University Hospitals Seidman Cancer Center, Cleveland, Ohio., CHU de Quebec-L'Hotel-Dieu de Québec, Montreal, Quebec., Sutter Cancer Centers Radiation Oncology Services-accruals under Radiologic Associates of Sacramento, Sacramento, California., Beaumont Health, Southfield, Michigan., Cedars-Sinai Medical Center, Los Angeles, California., Henry Ford Cancer Institute, Detroit, Michigan.