2025-2026 MCW Radiation Oncology Annual Report - Flipbook - Page 6
2025-2026 Medical College of Wisconsin, Radia琀椀on Oncology Annual Report
Charging Forward: Building Wisconsin’s First
Single Room Proton Therapy Program at Froedtert
& MCW
Physicists in the Department of Radia琀椀on Oncology at the Froedtert & the Medical College of Wisconsin are in
the final phase of commissioning a single-room proton therapy program designed to deliver highly precise
radia琀椀on treatment. The Mevion S250i with HYPERSCAN and Adap琀椀ve Aperture can deliver proton beam
energies up to 230 MeV, and is housed within an above-grade, mul琀椀story vault integrated into the core of the
hospital, with direct access to Radia琀椀on Oncology within the Specialty Clinics Building. This
ini琀椀a琀椀ve represents the culmina琀椀on of more than three years of planning, design, and implementa琀椀on, with
clinical opera琀椀ons an琀椀cipated to begin in March 2026, pending comple琀椀on of commissioning and regulatory
approvals.
A defining clinical advantage of proton therapy is its ability to deliver a rela琀椀vely low entrance dose proximal to
the Bragg peak compared with photon beams, owing to the absence of an extended buildup region, while also
having no exit dose beyond the target volume, a fundamental dis琀椀nc琀椀on from conven琀椀onal photon-based
radia琀椀on. This dose distribu琀椀on allows radia琀椀on to be deposited precisely within the tumor while substan琀椀ally
limi琀椀ng exposure to adjacent organs at risk and 琀椀ssue. By elimina琀椀ng exit dose and reducing unnecessary
integral dose to normal 琀椀ssues, proton therapy has the poten琀椀al to lower the risk of radia琀椀on-induced
secondary malignancies, par琀椀cularly in pediatric pa琀椀ents, and in individuals with long life expectancy. These
6
