An On-Line Tomographic Guidance System for Dose Escalation in Radiotherapy for Adenocarcinoma of the Prostate
Phase 1 of Final rept.
WILLIAM BEAUMONT HOSPITAL ROYAL OAK MI
Pagination or Media Count:
There is strong evidence to support the hypothesis that increasing radiation dose to the prostate will increase the probability of cure. A major difficulty in pursuing dose escalation is the toxicity induced in the surrounding normal tissues. These normal tissues are irradiated as a consequence of planning margins used to guarantee the delivery of the prescribed dose to the entire clinical target volume prostate and seminal vesicles. The margins are constructed from clinical knowledge of uncertainties in daily patient positioning and organ motion. In these investigations, a new imaging technology, cone-beam computed tomography CT was developed to localize the prostate and surrounding tissues on a daily basis, allowing the radiation field to be applied with great precision. By increasing precision, more conformal treatment fields can be applied, reducing the dose to surrounding normal tissues and allowing the safe pursuit of dose escalation. This new imaging modality, flat-panel based cone-beam CT, has been developed to permit soft-tissue imaging in the radiation therapy setting. Images acquired with this system are of sufficient quality to permit direction of the daily treatment, permitting dramatic 15 increases in dose escalation. The next major challenge is in the development of a clinical process to employ this valuable new information.
- Medicine and Medical Research