Measurement of the dose components of fast and thermal neutrons and photons from a 0.1 mg Cf-252 source in wafer for brachytherapy treatment planning

The use of Cf-252 in brachytherapy is expected to be more effective with th e therapy of bulky tumors than the conventional therapy with photons. For t reatment planning a code developed for calculation of gamma dose was used t o generate the dose distributions of fast and B-10 enhanced thermal neutron s and photons. Dose distributions of these components measured with ionizat ion chambers and a GM counter were fitted to analytical functions as requir ed by the modified treatment planning program. A comparison of these experi mental results and the treatment planning output indicate good agreement. T herefore, the program may be used to optimize the brachytherapy procedure c onsidering all three dose components. A realistic case of a patient being t reated with conventional brachytherapy has been used to calculate the dose distribution that would be obtained by use of the Cf-252 source. (C) 2000 A merican Association of Physicists in Medicine. [S0094-2405(00)01310-9].