Comparison of treatment plans for patients with high-grade brain tumors using two different treatment planning systems in radiotherapy

To compare treatment plans created using the Eclipse and Prowess treatment planning systems for patients diagnosed with high-grade brain tumors in the left temporal lobe and to evaluate target volume coverage and doses delivered to critical organs using intensity-modulated radiotherapy (IMRT) technique.

This retrospective comparative planning study included 15 patients. Plans were created on CT images using step-and-shoot IMRT with 6 MV photons. Eclipse used the Pencil Beam Convolution (PBC) algorithm, while Prowess used the Collapsed Cone Convolution (CCCS) algorithm. A total dose of 60 Gy in 30 fractions was prescribed. Dosimetric parameters were analyzed statistically.

Both TPSs achieved comparable target coverage, with no significant differences in conformity and homogeneity indices (p = 0.075 and p = 0.590, respectively) or dose-volume parameters (D95, D98, D2; p > 0.05). Eclipse provided significantly lower doses to the ipsilateral lens, brainstem, left optic nerve, cochlea, and whole brain V40 (p < 0.05).

Both TPSs demonstrated adequate target coverage; however, Eclipse achieved statistically significant dose reductions in several critical structures, which may have clinical relevance in reducing toxicity risk.