HOW DOES
POST-IMPLANT EDEMA IMPACT ON THE URETHRAL DOSE IN PROSTATE BRACHYTHERAPY?
M. Saiful Huq, Frank M. Waterman, and Adam P. Dicker
Supported in part by P30 CA 56036-03 (NCI)
Department of Radiation Oncology, Kimmel Cancer Center, Jefferson
Medical College, Thomas Jefferson University Hospital, Philadelphia, PA 19107
Results:
The prostate volumes decreased by 37 + 17 % during the interval between the 2
post-implant CT scans. As the prostate edema resolved, the spatial distribution of the
implanted seeds contracted with the prostate tissue, thereby increasing the dose rate in
the central portion of the prostate and the urethral dose. The D10 urethral
doses indicated by the second post-implant CT scans were from 5 % to 177 % higher (mean:
34 + 19 %) than those indicated by initial CT scans. The mean D10 urethra
dose in I-125 implants was 274 Gy based on the initial CT scan and 367 Gy based on the
later CT scan, an average increase of 93 Gy. The increase in the urethral dose is
correlated with the decrease in the prostate volume (correlation coefficient 0.641).
Purpose | Materials
and Methods | Results | Conclusions
Medical Physics Home
