In the treatment of prostate cancer using intensity-modulated radiation therapy (IMRT), investigation of the accuracy of the calculated doses center point of the axis and the referance depth with the different methods.
METHODS
In the study, 10 prostate IMRT plans were prepared to be
treated lineer accelerator. These plans were transfered to the
water equivalent solid phantom for quality control (QC) plans
of each patient. QC plans, gantry, collimator and table angles
of original and 0 degrees were created in two different ways.
The measurements were performed using film and ion chambers
with different volumes at 5 cm depth. Doses obtained
with measurement methods, were compared by calculated
doses in TPS.
RESULTS
QC plans prepared with actual angle and 0 degree of gantry,
collimator and table, the difference of dose between measured
and calculated by TPS were 3.87% and 1.26% with EBT3, respectively.
CONCLUSION
The agreement of calculated and measured doses, QC plans
prepared with gantry, collimator and table angle 0 is higher
than QC plans prepared with actual angles.