Potential improvement in the results of irradiation for prostate carcinoma using improved dose distribution

Results for radiation treatment of prostate carcinoma indicate that nearly one-third of Stage C patients fail locally. This number will likely increase as occult failures are discovered by monitoring serum prostate specific antigen levels. Thus, there is need for techniques that would increase the local control of prostatic carcinoma. Using cross-sectional imaging and 3-dimensional treatment planning, dose distributions for photon irradiation can be created that conform more closely to the shape of the prostate and seminal vesicles, sparing additional dose to portions of bladder and rectum. A dose escalation trial is underway to investigate whether these techniques will lead to increased local control without unacceptable increases in bladder and rectal complications. While zero local failures is probably an unattainable goal, reduction in local failure in prostate cancer would likely increase the overall cure rate in this disease.