Patent ID: 8546774

Claim:
An apparatus for delivering a biological dose at a treatment site of a patient, the apparatus comprising: a first component to determine a variability of relative biological effectiveness (RBE) along a line of each of a plurality of hadron beams, wherein RBE is a ratio of a dose of reference radiation to a hadron dose required to achieve a same biological effect; a second component to calculate RBE values at a plurality of sections of a spread-out Bragg peak (SOBP) associated with the treatment site, taking into account the determined variability; and a third component to adjust an intensity and energy of one of the plurality of hadron beams at each of the plurality of sections of the associated spread-out Bragg peak (SOBP) based on respective calculated RBE values for each of the plurality of sections to provide a calculated biological dose distribution for each of the plurality of sections, wherein the plurality of sections include: a declining distal edge area of the SOBP and at least one of: a proximal area of the SOBP, a distal area of the SOBP, a pre-plateau area of the SOBP, and wherein the calculated biological dose distributions superimpose to provide a desired biological dose at the treatment site.