Southwest Florida now has access to one of the most advanced cancer treatments in the country, with the opening of the region’s first proton therapy center.
Southwest Florida Proton on Jan. 8 showcased the only proton therapy system on Florida’s west coast during a media tour of its new 42,000-square-foot facility. The system is one of just 46 in the country and among a handful in Florida. The closest comparable system is in Miami.
“We’re very proud of what we created here,” said Dr. Arie Dosoretz, a managing partner of the center, which is located at the northwest corner of Three Oaks and Estero parkways in south Lee County.
Dr. Arie Dosoretz, CEO and managing partner of Southwest Florida Proton, addresses reporters during a tour of the new facility. Dosoretz spent five years planning the approximately $80 million project.
Sheldon Zoldan
The highlight of the tour was the treatment room itself. Patients lie on a table beneath the machine that delivers targeted proton beams to tumors. The system, manufactured in Belgium by IBA, includes a 110,000-pound accelerator and a 50,000-pound counterweight. It is housed in a three-story section of the building and took more than a year to install and calibrate.
The first patients began treatment during the final week of 2025. Seven patients were treated Jan. 8.
The center’s goal is to operate two eight-hour shifts, treating two to three patients per hour.
Southwest Florida Proton, a 42,000-square-foot facility at the northwest corner of Three Oaks and Estero parkways, houses the only proton therapy system on Florida’s west coast.
Southwest Florida Proton
Dosoretz began planning the project five years ago, navigating three hurricanes and the COVID-19 pandemic along the way. The approximately $80 million project includes Lee Health as a partner, with a diagnostic imaging center on-site. Advocate Radiation Oncology began offering conventional photon radiation therapy at the location about a year ago.
Proton therapy is more advanced than traditional photon radiation. It allows for greater precision and limits damage to surrounding healthy tissue by targeting tumors more directly. It is especially useful for tumors near vital organs, such as the heart or brain and is the preferred treatment for many pediatric cancers.
Dr. Shannon MacDonald, associate medical director of Southwest Florida Proton, speaks during a media tour of the region’s first proton therapy center on Jan. 8. MacDonald previously served on the faculty at Harvard Medical School and Massachusetts General Hospital.
Sheldon Zoldan
Dosoretz introduced Dr. Shannon MacDonald, who joined the center 11 months ago as associate medical director. She relocated from Boston, where she was an associate professor of radiation oncology at Harvard Medical School and served as director of the skull base service, director of the sarcoma service and proton therapy liaison at Massachusetts General Hospital.
MacDonald previously taught Dosoretz in medical school. The two reconnected at a medical conference, where he shared plans for the proton center, eventually persuading her to move to Southwest Florida to help lead it.
“We have a beautiful, single-room cyclotron and I’m very happy to work with that machine and many software systems we have here,” she said. “But mostly, I’m here to work with the people and the team that’s here. We have a great proton team.”