The use of ion beams therapy to treat cancerous tumors is motivated by the highly localized dose distribution. The high carbon mass (compared to proton) leads to a smaller angular spreading of the beam and a higher dose deposition at the end of the radiation range (i.e., at the Bragg peak). Moreover, the relative biological efficiency (RBE), is higher for carbon ions in the Bragg peak region. Therefore, carbon ions allow better targeting of the tumor while preserving the surrounding healthy tissues. To take advantage of carbon ions in radiotherapy, a very high accuracy dose deposition is required. The physical dose deposition is affected by the fragmentation of the ions along their penetration path in the human tissues.

This talk will discuss measurements of carbon fragmentation, required for proper carbon treatment planning. An alternative of treatment with lighter ion will also be presented.