It was aimed to compare two different planning algorithms (Pencil Beam and Convolution Superposition) with regard to lung dose-volume parameters obtained from the created 3-D conformal radiotherapy plans of lung cancer patients who had lobectomy/bilobectomy surgery.
METHODS
The treatment plans of 10 lung cancer patients administered
adjuvant 3-D conformal radiotherapy were evaluated in this
study. Using two different algorithms, calculations were performed
for 6 and 18 MV-X photon beams, respectively. The
differences on the relevant lung dose-volume parameters were
analyzed.
RESULTS
In terms of lung dose-volume parameters, the difference between
the algorithms was statistically significant in V5, V13
and V30 obtained from plans for 6 MV-X photon beam energy
(p=0.005; p=0.005; p=0.008, respectively).
CONCLUSION
Higher values were found especially in parameters expressing
“low dose area of lungs” for Convolution/Superposition algorithm
in radiotherapy planning. Convolution/Superposition
algorithm should be preferred to Pencil Beam algorithm due
to its increased accuracy in dose calculation in radiotherapy
planning.