2Department of Radiation Oncology, Acıbadem Altunizade Hospital, İstanbul-Türkiye
3Department of Radiation Oncology, İstanbul University Oncology Institute, İstanbul-Türkiye DOI : 10.5505/tjo.2024.4369 OBJECTIVE
The aim of our study is to analyze the changes in dosimetric parameters obtained in pre-planning (PP), intraoperative planning (IOP), and post-implant dosimetry (PID).
METHODS
The study focused on the prostate as the target volume, with the rectum and urethra designated as organs
at risk (OARs). Dosimetric differences between PP and IOP, PP and PID, and IOP and PID were
assessed, including parameters such as prostate dose and volumes D90, pV100, pV150; urethral doses
uD10, uD30, uD50; urethral volumes uV100, uV150; and rectal volumes rV100, rV150.
RESULTS
Comparing pD90 values between PP and IOP, PP and PID, and IOP and PID applications yielded p-values
of 0.393, <0.001, and <0.001, respectively. For pV90 values, comparisons between PP and IOP, PP
and PID, and IOP and PID showed p-values of 0.084, <0.001, and 0.001, respectively. No significant
differences were observed in pD90, pV100, uD50, uV100, or rV50 when comparing PP with IOP. Similarly,
no significant differences were found in uD50 or rV50 when comparing PP with PID. Comparing
IOP with PID revealed no significant differences in pV150, uD30, rV50, or pV150. However, significant
differences were found in all other parameters among the three applications.
CONCLUSION
The dose distribution in PP undergoes significant alterations due to edema formation and changes in
the placement of OARs. Although it was determined that there were changes in PID according to the PP
and IOP dose distribution, it was found to be compatible with the criteria reported in AAPM TG 137.