Marie-Catherine Vozenin

Marie-Catherine Vozenin is Professor and Director of the RadioBiology Laboratory in the Department of Radiation Oncology at Lausanne University Hospital (CHUV) and the University of Lausanne, Switzerland. She is the world's leading investigator of FLASH radiotherapy—an emerging paradigm in which radiation is delivered at ultra-high dose rates (greater than 40 Gy/s) orders of magnitude faster than conventional therapy. Vozenin's laboratory produced the landmark 2014 preclinical study demonstrating that FLASH irradiation spares normal intestinal tissue while maintaining equivalent tumor control compared to conventional dose-rate irradiation, igniting international scientific and clinical excitement around the FLASH effect. Vozenin has led a comprehensive translational research program characterizing the biological mechanisms underlying FLASH radioprotection, including investigations into transient oxygen depletion, reactive oxygen species dynamics, immune microenvironment modulation, and differential DNA damage and repair kinetics in normal versus tumor tissue. Her laboratory has established standardized dosimetric and biological methodologies for FLASH research that have been adopted by laboratories worldwide, helping to resolve early reproducibility challenges in the field. She has extended FLASH experiments from electrons to proton beams, contributing to the development of clinical-grade proton FLASH delivery systems. In 2019, Vozenin and her colleagues reported the first-ever clinical application of FLASH radiotherapy in a human patient—a woman with T-cell lymphoma cutaneous metastasis treated with electron FLASH at CHUV—demonstrating that the FLASH effect observed in preclinical models translated to human tissue with superior skin sparing compared to historical controls. This milestone opened the door to ongoing phase I clinical trials of FLASH RT for bone metastases, lung tumors, and pediatric brain tumors at multiple international centers. Vozenin's work has earned her numerous international prizes and positioned Lausanne as the global epicenter of FLASH radiotherapy science.