Evolution of hadron therapy from 1935 to 2005: a personal view.

Introduction: Hadron therapy is today an established modality in cancer radiation therapy that, world-wide, is available in about hundred centres. About 90% of them are devoted to proton therapy and the rest also to carbon ion therapy. Based on the superior ballistic and radiobiological properties of fast ions, this discipline experienced a remarkable growth in the last 30 years. Purpose: This paper reviews the history of hadron therapy starting from the initial work done at Berkeley in the 30's. Methods: Fast neutron therapy is not forgotten but the main accent is on the parallel development of proton and carbon ion therapy. For space reasons pion therapy, to which a lot of efforts have been devoted without success, is not discussed. Results: The activities of the main protagonists in USA, Japan and Europe are shortly presented so that the reader can appreciate the relevance of the contribution given by each of them to the advancement of the field. Conclusions: The review ends in 2005, when the carbon ion centres HIT in Heidelberg and CNAO in Pavia were under construction, with the aim of putting at the disposal of European citizens advanced treatments of radioresistant tumours, which cannot be effectively treated neither with X rays nor with protons. [ABSTRACT FROM AUTHOR]