Speaker
Description
External beam radiotherapy remains the standard of care for more than half of all cancer patients worldwide. In recent years, the use of very high energy electrons (VHEE) in the 50–250 MeV range has attracted considerable interest for radiotherapeutic applications, particularly in the treatment of deep-seated tumors. VHEE beams generated via laser-plasma acceleration (LPA) are characterized by ultra-short electron bunches and extremely high instantaneous dose rates, holding promise for their use in investigating ultra-high dose rate phenomena such as the FLASH effect. This compelling modality has demonstrated significant reductions in normal tissue toxicity and inflammation during external beam radiotherapy.
To advance research in this area, we have established a dedicated experimental platform at BELLA to study the biological effectiveness of VHEE produced by compact LPA technology. Robust beam delivery and dosimetry protocols have been developed to support the irradiation of biological samples within a purpose-built sample irradiation area. A set of normal and tumor cell lines, as well as a range of peptide samples, were irradiated using LPA VHEE bunches characterized by broad electron energy spectra spanning 50–200 MeV and a bunch charge of approximately 200 pC. Between 50 and 400 LPA bunches were accumulated to deliver total doses ranging from 5 to 20 Gy to the biological samples. Radiation damage was assessed through clonogenic survival assays and peptide oxidation analyses. These results were subsequently benchmarked against X-ray exposures conducted at the Advanced Light Source, utilizing ultra-high dose rate soft X-rays, as well as conventional dose rate irradiations performed with a 300 kVp X-ray tube.
This presentation introduces the newly established BELLA VHEE platform and highlights preliminary findings from the biological sample irradiation campaign.
Funding acknowledgement: This work was supported by the Lawrence Berkeley National Laboratory Laboratory Directed Research and Development (LDRD) funding provided by the Director.
| Working group | WG6 |
|---|