2017 Volume 65 Issue 2 Pages 93-98
Purpose : To evaluate the dosimetric differences between volumetric modulated arc therapy (VMAT) and three-dimensional conformal radiation therapy (3D-CRT) for locally advanced non-small cell lung cancer (NSCLC).
Materials and methods : A planning study was performed with the data of 17 patients with inoperable NSCLC who actually underwent definitive radiotherapy. VMAT and 3D-CRT plans were created for each patient. The primary objectives of these plans were to prescribe 60 Gy in 30 fractions to 95% of the planning target volume and to limit the dose delivered to the spinal cord to less than 50 Gy. The secondary objectives were to keep the doses delivered to other risk organs as low as possible.
Results : The 3D-CRT plans for two patients did not achieve the primary objectives, although they were achieved by the VMAT plans for these patients. In a comparison of the acceptable plans, the VMAT plans improved the dose conformity, V20 and mean dose of the lung, and V35 of the oesophagus. There were no significant differences in V10 or V5 of the lung, or the maximum dose and mean dose of the oesophagus.
Conclusion : The advantage of VMAT compared to 3D-CRT may facilitate appropriate use of VMAT for patients with locally advanced NSCLC.
