Dosimetric comparison of three-dimensional conformal radiotherapy and simplified intensity-modulated radiotherapy for non-small cell lung cancer

Objective To compare dosimetrie difference of treatment planning of three-dimensional conformal radiotherapy (3D-CRT) and simplified intensity-modulated radiotherapy (slMRT) for non-small cell lung cancer (NSCLC). Methods Ten NSCLC patients treaded by radiotherapy were investigated. 3D-CRT and slMRT plannings were designed for each patient. The prescribed dose was 60 Gy(2 Gy/f), the 95 % of the planning target volume was received with this dose for each patient. The dose was computed with treatment planning system of ADAC Pinnacle3 using convolution/superpasition algorithm. Two plans were compared according to the homogeneity index (HI) and conformity index (CI) of dosimetry in the planning target volume and the parameters of dose-volume histogram (DVH) in normal tissue. Results In the terms of HI and CI, sIMRT had slight vantages over 3D-CRT. In the terms of DVH, compared with 3D-CRT, mean lung dose, V5, V10 and V20 of slMRT reduced by 14.81 %, 17.88 %, 19.15 % and 27.78 %, respectively. The dosimetric differences were not statistically significant between 3D-CRT and sIMRT in terms of esophagus, heart and spinal cord. Conclusions For NSCLC, sIMRT has some irreplaceable advantages over 3D-CRT and is worth spreading in clinical work. Key words: Lung neoplasms;  Radiotherapy;  Three dimensional conformal;  Intensity modulated;  Dosimetry