Trend of Electron Modality Usage over the Last Five Years In a Large Academic Clinic
Abstract
Purpose
Electron beam therapy has been used for treating shallow tumors such as skin cancers and postoperative keloids because of its favorable surface‑dose characteristics and simple clinical workflow. These treatments are often delivered with a single field and visual setup, without kV or MV image guidance. Despite these advantages, many clinics have observed a steady decline in electron utilization. This study evaluates five‑year trends in electron beam usage across a large academic radiation oncology network and examines the clinical relevance of maintaining higher‑energy electrons.
Methods
The University of Maryland Medical Center (UMMC) operates five radiation oncology centers across Maryland, all using the ARIA EMR system. Electron treatment data from 2020 through 2024 were extracted to quantify the number of patients treated with each available electron energy. UMMC offers five electron energies: 6, 9, 12, 16, and 20 MeV. Annual electron usage and cumulative energy‑specific utilization were analyzed to identify patterns and shifts in clinical practice.
Results
Electron therapy usage declined from 168 patients in 2020 to 85 patients in 2024. Over the five‑year period, cumulative patient counts for each energy were 250 (6 MeV), 199 (9 MeV), 135 (12 MeV), 26 (16 MeV), and 1 (20 MeV). Lower energies (6–12 MeV) accounted for nearly all treatments, while higher energies were rarely used. Only one patient received 20 MeV treatment during the entire study period. The decline coincided with increased adoption of VMAT, IMRT, and 3DCRT for breast boosts and other superficial targets, replacing traditional electron plans.
Conclusion
Electron therapy usage has decreased significantly over the past five years, with minimal reliance on 20 MeV. Given its extremely limited clinical utility and higher maintenance burden, discontinuing the 20 MeV beam is expected to have negligible clinical impact and supports its decommissioning within the network.