METHODS
CTV, PTV, and OAR were outlined by utilization of Sim-Pro
(CMS-USA) using 5 mm slice spaced computed tomography
scans. For each patient, individual 4, 5, 6, and 7 field plans,
with 18 MV photons, were assessed with XiO (CMS-USA)
3D planning workstation.
RESULTS
In comparing the different techniques, the greatest rectal
sparing was achieved with the 5 field plan (Rectal:
5F V25%=59.90±6.8 Gy, 4F V25%=62.30±10.3 Gy, 6F
V25%=69.36±5.7 Gy, 7F V25%=61.32±7.3 Gy).
CONCLUSION
While all the techniques achieved the goal of optimal homogeneity
of CTV-PTV, 4F provided the lowest femoral doses.
The greatest rectal sparing was achieved with 5 field conformal
technique.
Keywords: Dose-volume histogram; conformal radiotherapy; prostate cancer; treatment planning
