ASTRO: Targeted radioactive therapy for recurrent prostate cancer, new SBRT approaches, 5DCT-guided imaging advances and more

(Press-News.org) Physicians and scientists from the UCLA Health Jonsson Comprehensive Cancer Center will share the latest research and clinical trial results at the 2025 American Society for Radiation Oncology (ASTRO) Annual Meeting, including studies on targeted radioactive therapy for recurrent prostate cancer, new approaches to stereotactic body radiation for prostate and head and neck cancers, advances in MRI- and 5DCT-guided imaging for more precise treatments, and innovations in patient-focused cancer education.

At this year’s scientific meeting, Dr. Amar Kishan, executive vice chair of radiation oncology at UCLA and co-director of the Cancer Molecular Imaging, Nanotechnology and Theranostics Program at the UCLA Health Jonsson Comprehensive Cancer Center, will present findings from the LUNAR clinical trial (Abstract 3), which looks at adding 177Lutetium-PSMA, a targeted radioactive therapy, as a treatment given before ablative radiotherapy for men with recurrent prostate cancer. The results will be highlighted during an oral presentation on Sunday, Sept. 28 at 1:10pm PDT in the San Francisco Ballroom and is part of the ASTRO news briefing on Monday, Sept. 29 at 11am PDT.  

Additionally, Dr. Drew Moghanaki, chief of thoracic oncology in UCLA’s department of radiation oncology, has been named a 2025 fellow of ASTRO. The recognition is awarded annually to physicians, physicists, and scientists in honor of their exceptional achievements and lasting contributions to the society, cancer research, education, patient care, and the field of radiation oncology, highlighting work that advances the critical role of radiation therapy in cancer treatment. 

“UCLA studies featured at this year’s ASTRO meeting offer exciting new insights into emerging radiation therapies and imaging technologies, pointing to innovative approaches to make cancer treatment safer, more precise, and more effective,” said Dr. Michael Steinberg, professor and chair of radiation oncology at the David Geffen School of Medicine at UCLA and director of Clinical Affairs at the UCLA Health Jonsson Comprehensive Cancer Center. “These presentations highlight the collaborative efforts of our physicians, scientists, and trainees, and reflect UCLA’s long-standing leadership and commitment to advancing cancer care.”

Highlights of noteworthy presentations by UCLA faculty at ASTRO include:

Abstract 148: Four-year results from SCIMITAR trial testing stereotactic body radiation therapy after prostate surgery

Dr. Jesus Juarez Casillas, co-chief resident in the department of radiation oncology at UCLA, will present findings from the SCIMITAR phase II clinical trial, which evaluated stereotactic body radiation therapy (SBRT) in men at risk of prostate cancer returning after surgery. After four years, 62% of patients had no signs of cancer returning, local recurrences were rare, and outcomes compared favorably with conventional radiation approaches. The research, led by Kishan, will be presented on Sunday, Sept. 28 at 5:05pm PDT in Room 24.

Abstract 253: 5DCT provides more accurate lung tumor imaging for patients with irregular breathing

Dr. Daniel Low, professor and vice chair of medical physics research and innovation in the department of radiation oncology at UCLA will report findings from the first large study of 5DCT, a new CT imaging technique designed to improve scans for patients with lung tumors who breathe irregularly. Unlike conventional 4DCT, which can produce unreliable images, 5DCT accounts for breathing motion in three dimensions as well as the rate and depth of each breath, producing clearer, artifact-free images. In a study of 108 patients, 5DCT allowed clinicians to more accurately define tumor size and motion, supporting better radiation planning. The workflow was reliable for nearly all patients, even those with highly variable breathing patterns, and is now being used to develop automated imaging processes such as 5D Cone-Beam CT. The results will be presented on Monday, Sept. 29 at 3:10pm PDT in in Room 155/157.

Abstract 1005: Comparing acute side effects of MRI-guided prostate SBRT with and without adaptive dose painting

Dr. Travis Courtney, co-chief resident in the department of radiation oncology at UCLA, is presenting research comparing two MRI-guided forms of targeted radiation therapy for prostate cancer. The study looked at standard high-dose MRI-guided stereotactic body radiotherapy (MRgSBRT) versus an adaptive “dose-painted” approach that boosts radiation to dominant tumor areas while lowering the dose to surrounding tissue. Results showed that patients receiving the adaptive dose-painted therapy experienced higher acute side effects as measured by physicians, particularly urinary and bowel symptoms. However, patient-reported quality-of-life outcomes were similar between the two groups. The findings suggest that increasing dose to specific tumor areas may not reduce side effects and highlight the need for further study as the trial continues to enroll patients. The work, led by Kishan, will be presented on Monday, Sept. 29 at 8:30am PDT in Room 307/308.

Abstract 1003: Analysis of sexual function after MRI-guided prostate SBRT in the MIRAGE trial

Dr. Jonathan Massachi, a radiation oncology resident at UCLA, will discuss findings from the MIRAGE trial that looked at sexual function in men receiving SBRT for prostate cancer, comparing standard CT-guided SBRT with MRI-guided SBRT. Despite using MRI guidance to reduce radiation exposure to key nerves and blood vessels, nearly one-third of men in both groups experienced a significant decline in sexual function two years after treatment. Factors such as hormone therapy, pelvic radiation, and baseline sexual function were linked to these changes. The findings suggest that while MRI-guided SBRT can reduce some radiation exposure, additional strategies, like vessel-sparing techniques, may be needed to better preserve sexual function in men undergoing prostate cancer treatment. The study, led by Kishan, will be presented on Monday, Sept. 29 at 8:20am PDT in Room 307/308.

Abstract 2785: Postoperative stereotactic body radiation therapy shows promise for head and neck cancer

Dr. Miriam Lane, a radiation oncology resident at UCLA, will present findings from a study evaluating postoperative SBRT for patients with newly diagnosed or recurrent head and neck cancer. The study found that SBRT was well-tolerated, with no severe acute side effects and only two late serious toxicities, though about half of patients experienced cancer recurrence within two years. Outcomes were similar for newly diagnosed and recurrent cases. The study, led by Dr. Ricky Savjani, an assistant professor of Radiation Oncology at the David Geffen School of Medicine at UCLA, suggests that postoperative SBRT is a feasible, shorter treatment option, while further research is needed to optimize patient selection and improve outcomes. The research will be presented on Monday, Sept. 29 at 10:45am PDT in Hall F.

Abstract 139: Study Identifies Genetic Drivers of Radiation-Resistant Prostate Cancer

Dr. Beth Neilsen, a former radiation oncology resident at UCLA, will discuss findings from a study that analyzed tumors from patients with prostate cancer that returned after radiation therapy. The research, led by Kishan, revealed that these recurrent tumors carry a higher frequency of mutations in genes linked to aggressive disease and faulty DNA repair, including BRCA1, BRCA2, RAD51B, and POLQ. Compared with treatment-naïve cancers, they also showed more aggressive molecular subtypes, higher genomic risk scores, and reduced androgen receptor activity. These insights shed light on why some prostate cancers resist radiation and may help guide future treatment approaches. The findings will be presented on Sunday, Sept. 28 at 3:30pm PDT in Room 155/157.

Session EDU 29: Empowering Patients through Innovation: Enhancing Cancer Education with Digital Tools 

Dr. Trudy Wu, assistant professor of radiation oncology at UCLA, will moderate a panel exploring how digital tools are transforming cancer education. Panelists Dr. David Grew, Dr. Hyunsoo No, and patient advocate Jill Feldman will share strategies for making complex cancer information, such as treatment options, side effects, and prognosis, more understandable and accessible. The session highlights narrated animations, educational videos, and patient-centered resources designed to reduce fear, improve understanding, and support better decision-making for patients navigating a cancer diagnosis. The session is on Monday, Sept. 29 at 5pm PDT in Room 152.

View the complete list of UCLA abstracts here.

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