Dosimetry evaluation and feasibility of intensity-modulated radiotherapy for non-small-cell lung cancer

Objective: To investigate the feasibility of intensity-modulated radiotherapy for non-small cell lung cancer with respect to target-dose conformity and heterogeneity and normal tissue sparing. Methods: In order to compare intensity-modulated and three-dimensional conformal radiotherapy of twenty non-small-cell lung cancer patients with stage I-IV, retrospective treatment planning study was performed. The two types of plans were designed to deliver 64 Gy to 95% of the planning target volume and to minimize the volume of normal lung, esophagus, heart and spinal cord irradiated above their tolerance doses. All plans were compared according to the planning target volume coverage, dose-volume histogram and other dosimetric parameters of normal tissues. Results: Commpared with three-dimensional conformal radiotherapy, the intensity-modulated plan improved conformity without significantly sacrificing the heterogeneity with regard to planning target volume coverage. The 1/20 and mean dose lung of were reduced with a median reduction of 11% and 2 Gy. Conclusions: It is indicated that intensity-modulated radiotherapy may be more applicable for non-small-cell lung cancer than three- dimensional conformal radiotherapy. (authors)