Report of the ACRO Resident Heidelberg Ion Therapy (HIT) Scholarship Experience
Faculty and Abstracts
Purpose: From May to June 2023 I underwent a course of training in carbon ion and other heavy charged particle therapy at the Heidelberg Ion Therapy Center (Heidelberg, Germany) through the ACRO Resident Heidelberg Ion Therapy Scholarship. I present my experience of that program, assess the value it added to my overall training, describe a collaborative research agenda that was initiated through my experience, and how lessons learned at the HIT will impact my career in the short and long-term.
Methodology: The typical daily schedule at the HIT is delineated with each activity described with reference to its contribution to training. Account is given of the research initiative begun during the scholarship including the process of establishing scholarly and resource collaboration as well as a broad outline of the project’s agenda and anticipated structure. The experience is then summarized from the standpoint of transition to an attending position that immediately followed.
Results: Days began with morning meeting consisting of chart review followed by 2-3 days per week presentations of journal club or research update by investigators. Then the list of cases prescribed proton therapy, carbon ion therapy, or combination ion therapy would be reviewed on electronic white board, and I would select 1-3 for initial contouring. Selections were made on the basis of variety, technical challenge, and expect clinical benefit of carbon ion therapy over low LET radiotherapy. I gained competency first in the use of Raystation Treatment Planning Software and then the definition and contouring of target volumes for heavy ion planning. Previously contoured cases with ready plans would be evaluated with physics. Carbon ion planning involves considerably more complex than photon or proton therapy including robust optimization based on RBE modeling and LET. Dose-volume histograms were compared with LET-volume histograms. Additionally I entered into collaboration with the Amir Abdollahi radiobiology laboratory on research into immunomagnetic nanoimaging of cancer stem cells, a novel technology I am developing using biologically-functionalized superparamagnetic iron oxide nanoparticles (SPIONs) to induce MRI-contrast enhancement of cancer stem cells of aggressive tumors with poor outcomes to conventional therapy. This imaging modality will be translated to a novel form of spatially fractionated radiation therapy exploiting focal escalation of LET to high biological risk targets with LET painting techniques, and optimized by organoid experiments determining threshold dose/LET parameters for cancer stem cell sterilization.
Conclusions: Shortly after concluding the HIT Scholarship, I graduated residency and started a faculty appointment at Mayo Clinic Florida. MCF will commission the first clinical heavy ion therapy program in the Americas. My career will be devoted to the use and optimization of this modality to change the natural history of aggressive/refractory cancers. Lessons learned through the HIT Scholarship experience will serve as the foundation to that pursuit.
