Plenary Presentation at The ASTRO Meeting by TGH Cancer Institute Member Dr. Rodney Ellis Demonstrated That Short-course Radiation Improves Quality of Life for Men with Prostate Cancer Without Compromising Outcomes

Phase III trial presented at ASTRO in San Francisco finds five-treatment regimen poised to become new standard of care.

SAN FRANCISCO, Sept. 29, 2025 /PRNewswire/ -- Men with intermediate-risk prostate cancer can receive a complete course of radiation in just five treatments — rather than the typical 20 to 28 — while maintaining excellent cancer control and improving quality of life, according to results of an international phase III trial conducted by Dr. Rodney J. Ellis.

The principal investigator of the trial, Ellis is a radiation oncologist and physician-scientist at the Tampa General Cancer Institute, Tampa General Hospital and serves as director of Clinical Research, Department of Radiation Oncology; and professor of Radiation Oncology, USF Health Morsani College of Medicine.

He presented the study results today (Monday, Sept. 29, 2025) in a plenary session at the American Society for Radiation Oncology (ASTRO) Annual Meeting.

The NRG Oncology GU-005 trial is among the first large, international Phase III randomized trials directly comparing stereotactic body radiotherapy (SBRT) with a longer course of moderately hypofractionated IMRT for men with localized, intermediate-risk prostate cancer, with co-primary endpoints of disease-free survival and patient-reported outcomes.

A total of 698 patients in six countries were randomly selected to receive either SBRT, delivered in five highly targeted treatments over two weeks, or IMRT, delivered in the standard 20 to 28 sessions over four to six weeks.

Two years after treatment, men treated with SBRT reported less decline in bowel function as part of the primary endpoint as well as secondary gains in sexual function and fewer problems with urinary control. Specifically:

• Bowel/rectal toxicity: Fewer SBRT patients reported clinically meaningful declines in bowel quality of life at two years (35% vs. 44% p=0.034)
• Sexual function: SBRT patients reported less decline in function at one year (34.3 % vs. 43.9%, p=0.026).
• Urinary incontinence: SBRT patients had significantly better scores at two years (25.9% vs. 34.7%, p=0.023).

Three years after treatment, both groups maintained high rates of disease-free survival (88.6% with SBRT vs. 92.1% with MH-IMRT). Overall survival was similarly high (91% vs. 94%).

"We demonstrated that patients treated with SBRT had fewer problems with urinary incontinence, better preservation of sexual function and significantly less rectal toxicity compared to those receiving longer-course radiation," Ellis said. "Equally important, the cancer outcomes were nearly identical between SBRT and IMRT in the previously published PACE-B trial at five years. These combined findings will likely change the standard of care for prostate cancer."

"This study reflects exactly the kind of research portfolio we continue to build at Tampa General in partnership with the USF Health Morsani College of Medicine: rigorous, care-defining clinical trials that translate into tangible benefits for patients," said Dr. Eduardo M. Sotomayor, vice president and executive director, TGH Cancer Institute. "That combination of scientific precision and patient impact is at the heart of our Cancer Institute's strategy to advance the latest research and improve care and treatment for individuals with cancer."

Prostate cancer is the most common solid tumor in men and intermediate-risk prostate cancer accounts for a substantial proportion of new prostate cancer diagnoses in the United States. Each year, tens of thousands of men could be eligible for the five-treatment course, which reduces treatment time by more than 80% compared to traditional regimens.

"For patients, this means less time away from work and family, fewer side effects and a treatment that is just as effective as what we've done for decades," Ellis said. "Knowing that we can both control the cancer and better preserve overall bowel function with additional improvements seen for both urinary and sexual function makes this a clear win for patients."

The trial provides insight into the biological trade-offs of treatment. While disease-free survival rates were similar, SBRT patients had a slightly higher rate of biochemical recurrence at three years (8% vs. 4%). Ellis emphasized that longer follow-up is needed to determine whether this difference reflects transient PSA "bounces" commonly seen after SBRT, rather than true cancer recurrence.

Pace-B gave a slightly higher total prostate dose and at 5 years showed SBRT was non-inferior to 5 to 8 weeks of daily IMRT, but with slightly higher bowel toxicity. GU-005 shows that careful planning and daily delivery can overcome the risk for toxicity and may benefit from focal targeted dose escalation to the regions of the prostate shown theoretically to harbor higher burden of disease. Current studies and routine clinical practices already are offering patients this option.

How it works
SBRT uses advanced imaging, fiducial markers and daily image guidance to deliver high doses of radiation directly to the prostate and, when possible, the portion of the prostate with the cancerous lesion. With such millimeter precision, this treatment reduces exposure of nearby organs such as the rectum and bladder. The precise radiation targeting allows SBRT to complete treatment in just five sessions, compared with several weeks of daily therapy with IMRT.

"The precision of modern SBRT is what makes this possible," Ellis explained. "By using daily imaging and careful dose constraints, we can safely escalate the dose to the tumor while protecting bowel and bladder function. Fewer doses mean fewer trips to the hospital and is one reason patients do better — not just in terms of convenience, but also quality of life."

Context and Next Steps
Until now, evidence supporting SBRT came largely from smaller, single-institution studies and the recent international PACE-B trial, which established non-inferiority but reported somewhat higher toxicity. By contrast, GU-005 showed lower rates of bowel and urinary side effects, likely due to stricter protocol requirements such as mandatory MRI fusion and daily image guidance.

"These results will accelerate the shift toward five-treatment SBRT for many men with localized, intermediate-risk prostate cancer," said Dr. Abraham Schwarzberg, executive vice president; chief of Oncology; president, Tampa General Provider Network, Tampa General Hospital and co-vice president, Clinical & Translational Research, TGH | USF Health Office of Clinical Research.

"The evidence is clear that we can shorten therapy, improve important aspects of quality of life and preserve outcomes — exactly the kind of change that patients value," Schwarzberg continued. "It also underscores the importance of our academic partnerships: By aligning Tampa General's clinical depth with USF Health Morsani College of Medicine, we are able to bring leading-edge protocols to our region and move the standard of care forward."

"With GU-005 and PACE-B together, we now have definitive, phase III evidence that five-treatment SBRT is safe, effective — and in many cases superior to longer regimens," Ellis said. "This will move forward recognition of SBRT as the preferred approach, and I expect it will quickly become the standard of care."

Attribution to the American Society for Radiation Oncology (ASTRO) Annual Meeting is requested in all coverage.

Study/Presentation Details
Abstract LBA 01: NRG-GU005: Phase III trial of SBRT vs. hypofractionated IMRT for intermediate-risk prostate cancer
Plenary Session: Monday, September 29, 2025, 2:06-2:16 p.m. Pacific Time, Walter E. Washington Convention Center, San Francisco
ClinicalTrials.gov Identifier: NCT03367702

ABOUT ASTRO
The American Society for Radiation Oncology (ASTRO) is the largest radiation oncology society in the world, with more than 10,000 members who are physicians, nurses, biologists, physicists, radiation therapists, dosimetrists and other health care professionals who specialize in treating patients with radiation therapies. Radiation therapy contributes to 40% of global cancer cures, and more than a million Americans annually receive radiation treatments for cancer. For information on radiation therapy, visit RTAnswers.org. To learn more about ASTRO, visit our website and follow us on social media.

ABOUT TAMPA GENERAL HOSPITAL
Tampa General Hospital, the Tampa Bay region's only academic health system, is a 1,529-bed not-for-profit network of hospital and outpatient services spanning across Florida. As the only center for Level l trauma and comprehensive burn care center serving 23 counties, Tampa General  delivers world-class care. The system's hospitals include Tampa General Hospital, Tampa General Rehabilitation Hospital, Tampa General Behavioral Health Hospital, all in Tampa; Tampa General Brooksville, Tampa General Spring Hill and Tampa General Crystal River. Tampa General is the highest-ranked hospital in Tampa Bay in U.S. News & World Report's 2025-2026 Best Hospitals, with six medical specialties ranking among the top 50 in the nation and five additional medical specialties ranked among the top 10% best hospital programs in the United States. As the first hospital in Florida to open a clinical command center for real-time situational awareness, the academic health system has elevated its digital care coordination center to the next level by leveraging artificial intelligence (AI) and its analytics platform across inpatient and outpatient care to ensure patients receive leading-edge care as quickly and safely as possible. Tampa General's commitment to growing and developing its team members is recognized by three prestigious Forbes magazine rankings — in the 2025 America's Best Large Employers, the top 50 in Florida in the 2024 America's Best Employers by State and the 2023 America's Best Employers for Women.

Tampa General is the area's safety-net hospital, caring for anyone regardless of ability to pay; in fiscal year 2023, Tampa General provided a net community benefit of approximately $301.8 million in the form of health care for underinsured patients, community education and financial support to community health organizations in Tampa Bay. It was the nation's No. 1 adult solid organ transplant center in 2024 and is the primary teaching hospital for the USF Health Morsani College of Medicine. With five medical helicopters, Tampa General transports critically injured or ill patients from surrounding counties to receive the advanced care their conditions require. Tampa General has a nationally accredited comprehensive stroke center and its 32-bed Neuroscience, Intensive Care Unit is the largest on the West Coast of Florida. It is home to the Muma Children's Hospital at TGH, the Jennifer Leigh Muma 82-bed neonatal intensive care unit and a nationally accredited rehabilitation center. Tampa General's footprint includes TGH North, which consists of three hospitals and several outpatient locations in Citrus and Hernando counties; 17 Tampa General Medical Group Primary Care offices; TGH Family Care Center Kennedy; two TGH outpatient centers; TGH Virtual Health; and 19 TGH Imaging outpatient radiology centers throughout Hillsborough, Pasco, Pinellas and Palm Beach counties. Tampa Bay area residents receive world-class care from the TGH Urgent Care, powered by the Fast Track network of clinics. To see a medical care professional live anytime, anywhere on a smartphone, tablet or computer, visit Virtual Health | Tampa General Hospital (tgh.org). For more information, go to www.tgh.org.

Media Contact: Beth Hardy, APR
Assistant Manager
Publications & Physician Communications
(727) 510-6363 (cell)
[email protected]

SOURCE Tampa General Hospital