Work in progress: treatment planning system for conformation radiotherapy.

Conformation radiotherapy is a treatment technique that allows the high-dose region in the treatment field to be shaped to the prescribed treatment volume. The algorithms and software for obtaining a complete dose distribution needed to plan conformation radiotherapy for patients have been developed and implemented on the Modulex RTP system, manufactured by Computerized Medical Systems, Inc. Standard beam data, i.e., tissue-phantom ratios and off-center ratios, were used to calculate asymmetric dose profiles for the irregular field at any gantry angle. Computed dose distributions were compared with measured dose distributions and agreement was within 5% in the high-dose region.