Radiation oncology is a rapidly evolving discipline that harnesses high-energy radiation to treat cancer, offering a non-invasive alternative or complement to surgery and systemic therapies. Dr. Yashar’s expertise lies in advanced radiation techniques such as intensity-modulated radiation therapy (IMRT), image-guided radiation therapy (IGRT), and brachytherapy. These modalities are critical for delivering radiation doses with sub-millimeter accuracy, selectively targeting tumor cells while sparing surrounding healthy tissue. Such precision mitigates side effects and amplifies therapeutic efficacy, especially in complex cancers like breast and gynecologic malignancies. Under Dr. Yashar’s leadership, these technologies have been integrated into clinical protocols that prioritize both patient safety and outcome optimization.

Further underscoring her impact, Dr. Yashar holds multiple prominent leadership roles within UC San Diego, including vice chair of clinical affairs for radiation medicine and applied sciences, associate dean at the School of Medicine, and chair of the UC San Diego Health Sciences Faculty Council. This comprehensive involvement in academic, clinical, and administrative spheres fuels her advocacy for multidisciplinary approaches essential to modern oncology. She emphasizes that effective cancer care transcends isolated medical treatments, requiring tight collaboration between medical, surgical, and radiation oncologists as well as nursing staff, social workers, and nutrition experts, collectively addressing the full spectrum of patient needs from diagnosis through survivorship.

Health policy reform remains a cornerstone of Dr. Yashar’s agenda. As the current chair of ASTRO’s health policy council, she champions legislation like the Radiation Oncology Case Rate (ROCR) Act, presently under congressional review. This bill aims to stabilize reimbursement mechanisms for radiation oncology, ensuring funding is aligned with evidence-based guidelines while safeguarding access for underserved populations. By advocating for value-based care, Dr. Yashar and ASTRO seek to dismantle administrative inefficiencies and promote equitable distribution of resources, ultimately enhancing healthcare quality across diverse patient demographics.

Central to Dr. Yashar’s vision is the commitment to innovation-driven oncology care. Emerging technologies, including adaptive radiation therapies that adjust in real-time to tumor changes, and integration of artificial intelligence for treatment planning, are pivotal frontiers under her stewardship. These advances facilitate increasingly tailored treatment regimens, dynamically responding to tumor biology and patient-specific factors. Such precision medicine paradigms represent the future of radiation oncology, optimizing therapeutic ratios, reducing toxicities, and improving patient prognoses on an individualized basis.

Dr. Yashar’s work is situated within the renowned Moores Cancer Center at UC San Diego Health, an academic hub famed for its comprehensive, multidisciplinary approach. At Moores, multidisciplinary tumor boards convene specialists across disciplines to devise patient-centric strategies, blending clinical expertise with clinical trial opportunities and psychosocial support services. This holistic model ensures that each patient’s care pathway addresses medical, emotional, and financial challenges, highlighting the critical interplay between scientific innovation and compassionate healthcare delivery.

Her leadership has also elevated the national profile of Moores Cancer Center and UC San Diego’s oncology services. According to Diane Simeone, MD, the center’s director, Dr. Yashar’s appointment as ASTRO president-elect serves as a testament to her far-reaching influence and longstanding dedication. It brings broader attention to the center’s multifaceted cancer program, which spans the continuum from fundamental research and disease prevention to treatment innovation and survivorship care. This alignment accelerates progress in cancer care, fostering an environment where breakthroughs can rapidly translate into improved patient outcomes.

Importantly, Dr. Yashar emphasizes the need to protect evidence-based clinical guidelines that underpin radiation oncology practice. Amidst a changing healthcare landscape, she warns against policies that create administrative burdens or stifle innovation, advocating instead for systems that incentivize quality, efficiency, and equity. Her stance champions the principle that cancer care must be accessible, scientifically rigorous, and sustainably funded, ensuring that both current patients and future generations benefit from continual advances.

Her presidency will continue ASTRO’s mission to foster education, research, and advocacy in radiation oncology. Dr. Yashar’s extensive leadership experience, including a prior presidency of the American Brachytherapy Society and trusteeship of the American Board of Radiology, equips her with unique insights into both the clinical and policy dimensions of cancer care. She oversees national board certification processes, ensuring rigorous standards for the next generation of specialists committed to delivering state-of-the-art radiation oncology.

UC San Diego Health itself stands as a leader in comprehensive cancer care, nationally ranked in 10 specialties by U.S. News & World Report and recognized for its academic excellence by Vizient, Inc. The institutional emphasis on integrating research, clinical care, and community engagement mirrors Dr. Yashar’s vision for radiation oncology: a patient-centered, innovative, and equitable discipline poised to transform cancer outcomes. As she prepares to assume the full responsibilities of ASTRO’s presidency in 2026, her focus remains squarely on enhancing clinical pathways, expanding access, and fostering collaboration that bridges technology and humanity in the fight against cancer.

In Dr. Yashar’s own words, continued progress hinges on sustained support for research and intelligent clinical decision tools that elevate care quality and fairness. Her presidency promises to advance radiation oncology as a leader in informed and compassionate cancer treatment, ensuring that novel therapies reach patients effectively while preserving the ethical standards of medical practice. Under her influence, the field is poised not only to improve survival rates but also to enhance quality of life for millions affected by cancer worldwide.

The appointment of Dr. Catheryn Yashar exemplifies the intersection of scientific innovation, clinical excellence, and policy advocacy critical for the future of oncology. As cancer care becomes ever more technologically sophisticated and data-driven, her leadership will guide a community dedicated to translating emerging evidence into real-world benefits. This marks an exciting chapter for radiation oncology, as it embraces advances that promise greater precision, fewer side effects, and more equitable access to life-saving treatments.

Subject of Research: Radiation oncology, advanced radiation therapies, health policy in cancer care

Article Title: Dr. Catheryn Yashar Named President-Elect of ASTRO, Leading Advances in Precision and Equitable Radiation Oncology

News Publication Date: Not specified

Web References:

• https://www.astro.org/
• https://providers.ucsd.edu/details/11567/radiation-oncology-cancer
• https://www.astro.org/news-and-publications/news-and-media-center/news-releases/2025/rocr-act-2025-press-release

Image Credits: Leslie Aquinde, UC San Diego Health

Keywords: Radiation oncology, breast cancer, gynecologic cancer, health care, cancer, radiology

Radiotherapy remains a cornerstone treatment modality for early-stage breast cancer, particularly following breast-conserving surgery. However, one of the persistent issues radiologists face is ensuring that the planned radiation dose corresponds exactly to the dose delivered throughout the treatment course. Traditional dosimetric verification methods often lack the capability to capture subtle inter- and intra-fractional variations that can accumulate and impact therapeutic outcomes. The integration of EPID with advanced imaging modalities like fan-beam CT marks a significant leap forward in overcoming these limitations.

The study underpinning this breakthrough engaged twenty-six patients diagnosed with early-stage breast cancer undergoing post-breast-conserving radiotherapy. By employing image-guided radiation therapy (IGRT) techniques alongside EPID dose validation, the researchers could dynamically assess dose delivery amid anatomical and positional shifts. The pivotal advantage lies in combining the high-resolution anatomical detail of FBCT with the real-time dosimetric feedback from EPID, enabling more adaptive and precise treatment control.

Quantitative evaluation of treatment adherence hinged upon gamma pass rates (2D γ-pass rate), specifically analyzing 3%/3 mm and 5%/3 mm criteria. These metrics are standard in dosimetry to compare measured doses with planned doses, with higher pass rates signaling better conformity. Findings revealed the IGRT group consistently achieved significantly higher gamma pass rates than their non-IGRT counterparts, signifying improved agreement between planned and delivered dose distributions. Notably, the subset receiving combined fan-beam CT guidance outperformed the IGRT-only group, underscoring the critical role of precise imaging in dose validation.

Target volume dosimetric parameters, including primary gross tumor volume (PGTV) D95 and D2, as well as planning target volume (PTV) D95 and D90, further elucidated the impact of this integrated approach. These parameters represent key dose-volume statistics that reflect the completeness and uniformity of tumor irradiation. In patients with left-sided breast cancer, significant statistical variations were detected in heart-related metrics such as mean dose (Dmean) and volume receiving 5 Gy (V5), together with lung V5. These findings highlight how inter-fractional anatomical shifts influence not only tumor coverage but also critical organ doses, reaffirming the necessity of image-guided dose adaptation.

Intriguingly, intra-fractional variations — those occurring within a single treatment session — also manifested significant effects on dosimetric outcomes. With the exception of the cardiac mean dose in some cases, the shifts observed during treatment deliver real-time challenges to dose accuracy, emphasizing the importance of real-time or near-real-time validation tools like EPID. By integrating the continuous dose monitoring capability of EPID with FBCT’s anatomical insights, clinicians gain a powerful, dual-perspective tool to detect and correct deviations promptly.

Right breast cancer patients echoed similar patterns, as all dose distribution parameters studied exhibited statistically significant sensitivity to inter- and intra-fractional differences. Such consistency across laterality underscores the robustness of the combined EPID and FBCT methodology regardless of tumor location. The approach effectively mitigates uncertainties arising from patient motion, organ deformation, and setup variability — factors that historically compromised treatment precision.

This technology also bears potential to refine radiotherapy margins, possibly reducing the extent of healthy tissue irradiation without sacrificing tumor coverage. Traditionally, generous margins are added to compensate for movement and positioning errors, inadvertently increasing risk to adjacent critical structures. The use of real-time in vivo dose validation may enable a shift toward individualized, margin-adaptive treatment planning, advancing both efficacy and safety.

Moreover, the study’s retrospective analysis method provides a strong model for future clinical validation studies. By evaluating treatment data post hoc while leveraging detailed imaging and dosimetric information, researchers can enhance understanding of dose delivery dynamics and guide the development of more refined radiotherapy protocols. This retrospective integration of EPID and FBCT data provides compelling evidence supporting a routine clinical role for these technologies.

The implications extend beyond breast cancer alone; the combined EPID and FBCT dose validation paradigm could be adapted to various radiotherapy domains where precise dose delivery is critical. Cancers with complex geometries, mobile target volumes, or proximity to sensitive organs stand to benefit from such advancements. The continual improvements in imaging speed, dose calculation algorithms, and real-time data processing further enable the operationalization of these systems in busy clinical workflows.

Looking ahead, one remarkable avenue is the advancement of adaptive radiotherapy strategies powered by integrated dose validation. Feedback generated during each session may inform immediate plan adjustments, dynamically mitigating deviations. Real-time data assimilation is poised to usher an era where radiotherapy evolves from a static plan-based treatment to a continuously optimized process tailored to evolving patient anatomy and tumor response.

In sum, the study validates a transformative combination of EPID and fan-beam CT guidance as a robust, accurate, and clinically feasible means of in vivo dose validation in post-breast-conserving radiotherapy for early-stage breast cancer. This approach represents an important step toward more personalized, safe, and effective radiation treatments. As radiotherapy precision advances, patient outcomes should correspondingly improve, reducing the incidence of adverse effects and enhancing local tumor control.

The intersection of dosimetry, imaging science, and radiation oncology embodied in this research paves a new path forward for cancer therapy delivery. With growing adoption, this methodology is likely to become a benchmark standard, guiding future innovations in treatment monitoring and verification.

For patients and clinicians alike, the ability to verify delivered dose with high fidelity in real time constitutes a significant reassurance and a foundation for therapeutic confidence. Further multi-center trials and technological refinements will continue to refine this promising frontier in oncologic care.

Subject of Research: Validation of in vivo radiation dose delivery during post-breast-conserving radiotherapy in early-stage breast cancer using EPID combined with fan-beam CT image guidance.

Article Title: Validation of in vivo dose using EPID combined with fan-beam CT guidance in post-breast-conserving radiotherapy for early-stage breast cancer.

Article References:
Zhu, W., Fang, J., Zhang, Y. et al. Validation of in vivo dose using EPID combined with fan-beam CT guidance in post-breast-conserving radiotherapy for early-stage breast cancer. BMC Cancer 25, 667 (2025). https://doi.org/10.1186/s12885-025-13431-6

Image Credits: Scienmag.com

DOI: https://doi.org/10.1186/s12885-025-13431-6