The University of Maryland School of Medicine and Advanced Particle Therapy LLC of San Diego, Calif., have broken ground on a new, more than $200 million proton treatment center, bringing to Maryland for the first time the most advanced radiation technology in cancer treatment. It will be just the 12th proton treatment center in the United States, and the only one in the Baltimore-Washington region. The facility will be housed in an 110,000-square-foot building in the University of Maryland BioPark on the University of Maryland’s founding campus in Baltimore. The building will include space for retail.