BOSTON, Oct. 28, 2012 (GLOBE NEWSWIRE) -- Patients undergoing treatment for prostate cancer using proton beam therapy (PBT) reported a higher quality of life (QOL) in early follow-up with similar QOL scores at two years compared to 3D conformal (3-D CRT) and intensity modulated radiation therapy (IMRT), according to research presented today at the American Society for Radiation Oncology's (ASTRO's) 54th Annual Meeting.
This non-randomized study evaluated the side effects of all three therapies with data from 94 patients who were treated with PBT, 123 patients who were treated with 3-D CRT and 153 patients who were treated with IMRT. At the first follow-up, 2-3 months following therapy, patients treated with PBT reported minimal bowel problems, however, patients treated with 3-D CRT and IMRT reported modest yet significant problems with bowel function. IMRT patients reported modest yet significant urinary problems at their first follow-up, while patients treated with PBT did not report similar problems until 12 months after treatment. Two years after treatment, patients undergoing all three forms of radiotherapy reported no significant problems with urination and similar problems with bowel function. Patients in all three treatment groups reported steadily worsening sexual function over the two-year study period.
This study used two validated QOL instruments to evaluate the outcomes of 370 patients during the 24-month period following treatment. The median patient age was 64 for those receiving PBT, 70 for those receiving 3-D CRT and 69 for those receiving IMRT. Treatment dose range was 74-82 Gy RBE for PBT, 66.4-79.2 Gy for 3-D CRT and 75.6-79.2 Gy for IMRT. Patients who were treated with PBT at the Massachusetts General Hospital and 3-D CRT at Harvard-affiliated hospitals were followed using the Prostate Cancer Symptoms Index (PCSI) instrument. The data for patients treated with IMRT was collected by the Prostate Cancer Outcomes and Satisfaction with Treatment Quality Assessment (PROST-QA) consortium using the Expanded Prostate Cancer Index Composite (EPIC) instrument. Baseline mean QOL scores were compared to scores at the first follow-up (two to three months after treatment) and again at 24 months using a paired t-test to assess whether the means were statistically different from each other. Clinically meaningful differences in QOL scores were defined as those exceeding half the standard deviation of the baseline mean score.
"Our study provides a unique addition to existing research in this field and suggests that patients undergoing proton beam therapy for prostate cancer may experience fewer immediate side effects," said Phillip J. Gray, MD, lead author of the study and a resident in the Harvard Radiation Oncology program in Boston. "Given the inherent limitations of any retrospective study, a prospective randomized controlled trial to investigate these differences will provide the most rigorous and valid comparison of these advanced technologies." The Massachusetts General Hospital and University of Pennsylvania have partnered and recently launched a randomized comparison of PBT and IMRT for patients with localized prostate cancer, under the direction of principal investigators Jason A. Efstathiou, MD, DPhil (the senior author of this study) and Justin Bekelman, MD. The trial is expected to open at several other proton centers next year.
The abstract, "Patient-Reported Quality of Life in Prostate Cancer Patients Treated With 3D Conformal, Intensity Modulated or Proton Beam Radiotherapy," will be presented in detail during a scientific session at ASTRO's Annual Meeting at 1:45 p.m. Eastern time on Sunday, October 28, 2012. To speak with Dr. Gray, call Michelle Kirkwood on October 28-31, 2012, in the ASTRO Press Office at the Boston Convention & Exhibition Center at 617-954-3461 or email michellek@astro.org.
ASTRO's 54th Annual Meeting, held in Boston, October 28-31, 2012, is the premier scientific meeting in radiation oncology and brings together more than 11,000 attendees including oncologists from all disciplines, medical physicists, dosimetrists, radiation therapists, radiation oncology nurses and nurse practitioners, biologists, physician assistants, practice administrators, industry representatives and other health care professionals from around the world. The theme of the 2012 Annual Meeting is "Advancing Patient Care Through Innovation" and examines how innovation in technology and patient care delivery can lead to improved patient outcomes. The four-day scientific meeting includes six plenary papers and 410 oral presentations in 63 oral scientific sessions, and 1,724 posters and 130 digital posters in 18 tracks/topic areas.
ABOUT ASTRO
ASTRO is the largest radiation oncology society in the world, with more than 10,000 members who specialize in treating patients with radiation therapies. As the leading organization in radiation oncology, biology and physics, the Society is dedicated to improving patient care through education, clinical practice, advancement of science and advocacy. For more information on radiation therapy, visit www.rtanswers.org. To learn more about ASTRO, visit www.astro.org.
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2012 American Society for Radiation Oncology (ASTRO) 54th Annual Meeting
News Briefing, Tuesday, October 30, 3:15 p.m. – 4:00 p.m., Eastern Time
Scientific Session: October 28, 2012, 1:45 – 3:15 p.m. ET, Boston Convention & Exhibition Center
30 Patient-Reported Quality of Life in Prostate Cancer Patients Treated With 3D Conformal, Intensity-Modulated or Proton Beam Radiotherapy
P. J. Gray1, J. J. Paly2, B. Yeap2, M. G. Sanda3, J. A. Talcott4, H. M. Sandler5, J. M. Michalski6, D. A. Hamstra7, J. E. Bekelman8, J. A. Efstathiou2, 1Harvard Radiation Oncology Program, Boston, MA, 2Massachusetts General Hospital, Boston, MA, 3Beth Israel Deaconess Medical Center, Boston, MA, 4Continuum Cancer Care Consortium, New York, NY, 5Cedars-Sinai Medical Center, Los Angeles, CA, 6Washington University School of Medicine, St. Louis, MO, 7University of Michigan Medical Center, Ann Arbor, MI, 8University of Pennsylvania, Philadelphia, PA
Purpose/Objectives: Limited data exist comparing contemporary technologies in the treatment of prostate cancer. 3D conformal (3-D CRT), proton beam (PBT) and intensity-modulated radiation therapy (IMRT) are all widely-used techniques for delivering high-dose radiation. We evaluated patient-reported outcomes (PRO) for quality of life (QOL) from three modern cohorts treated with each of these modalities.
Materials/Methods: QOL data for 153 patients treated with IMRT monotherapy and collected by the PROST-QA consortium using the Expanded Prostate Cancer Index Composite (EPIC) instrument were compared to data for 94 patients treated at the Massachusetts General Hospital with PBT monotherapy and 123 patients treated at Harvard-affiliated hospitals with 3-D CRT monotherapy and followed using the Prostate Cancer Symptoms Index (PCSI) instrument. PCSI scores were inverted for comparison to EPIC. Mean scores at baseline, at first follow-up (2-3 months) and at 24 months were compared using a paired t-test. To maintain the overall type 1 error at 0.05 after multiple comparisons, a p-value of 0.006 was considered significant. Clinically meaningful differences in QOL scores were defined as those exceeding half the baseline standard deviation.
Results: Distribution of Gleason score, T-stage and baseline PSA were similar in the PBT and IMRT cohorts but the 3-D CRT cohort had higher baseline PSA and more patients with T3 disease. Median patient age was 69 for IMRT, 70 for 3-D CRT and 64 for PBT (p less than .0001). Treatment dose range was 75.6-79.2 Gy for IMRT, 74-82 Gy RBE for PBT and 66.4-79.2 Gy for 3-D CRT. At the first survey post-treatment 3-D CRT and IMRT but not PBT were associated with significant and clinically meaningful lower mean bowel QOL scores (see table); all groups had significant decreases in bowel QOL scores at 24 months. Significantly lower scores in the urinary irritation domain were also seen at first follow-up for all 3 groups but this was clinically meaningful only in patients receiving IMRT. Sexual function domain scores were all lower but not clinically meaningful at 24 months.
Conclusions: In this non-randomized comparison using two validated QOL instruments, PBT appears to be associated with better early gastrointestinal QOL compared to 3-D CRT and IMRT with similar mild effects at later time points. While subject to selection bias, these preliminary data suggest transient differences in PRO between IMRT and PBT underscoring the rationale for a randomized controlled trial.
Disclosure Block:
P.J. Gray: None. J.J. Paly: None. B. Yeap: None. M.G. Sanda: None. J.A. Talcott: None. H.M. Sandler: None. J.M. Michalski: None. D.A. Hamstra: None. J.E. Bekelman: None. J.A. Efstathiou: None.
CONTACT:Michelle Kirkwood, 703-286-1600, michellek@astro.org