From 1954 through December 2013, more than 120 000 patients across the world have been treated with particle therapy, including more than 13 000 (10.8%) with carbon ions and more than 105 000 (87.5%) with protons (Table). More than 30% of those patients have been treated for ocular melanomas. Global acceptance of particle therapy is growing, with the most rapid increase in facilities occurring in Japan and the United States. Five particle facilities were opened in 2013 in Seattle, Washington; St. Louis, Missouri; Essen, Germany; and Nagoya and Tosu, Japan. The Figure, a and b, shows the rapid rise in patients treated, particularly with proton therapy and particularly in Japan and the United States.
Today, about 10 new facilities are in the phase of technical commissioning, clinical commissioning, or both, and 5 or 6 of them should be ready to treat patients before the end of 2014.