Protons Offer Reduced Cardiopulmonary Exposure for Patients Receiving Radiation Therapy for Esophageal Cancer

The purpose of this study is to investigate methods of minimizing radiation induced perioperative cardiopulmonary complications. Ten patients with esophageal cancer treated with radiation therapy between 2010 and 2013 were included in this study. Three separate plans were generated for each patient: 3D proton plan, 3D photon plan, and IMRT plan. A dose of 50.4Gy given in 28 fractions was delivered to the PTV allowing 90% isodose coverage of at least 95% of the PTV. Dose distributions of proton, 3D conformal photon, and intensity modulated radiation therapy (IMRT) treatment plans in patients with esophageal carcinoma were examined, focusing specifically on dose reduction to cardiac and pulmonary structures. Dose-volume histograms were calculated and analyzed in order to compare plans. The 3D proton plans showed decreased dose to partial volumes of the entire heart, arteries, and left ventricle in comparison to both the IMRT and 3D photon plans. The IMRT plans showed decreased dose delivered to the LAD artery, pericardium, and left atrium in comparison to the 3D photon plans (See Table). For patients receiving radiation therapy for esophageal cancer, proton plans are technically feasible with adequate coverage and may results in lower dose to cardiac structures. This may result in decreased cardiopulmonary toxicity and less morbidity to esophageal cancer patients.Scientific Abstract 2308; TableProtonIMRT3D PhotonProton vs IMRTProton vs 3D photonIMRT vs 3D photonHeart V30 (%)20.85±7.1242.28±15.332.72±9.390.0010.0050.109 V40 (%)16.21±6.3525.45±10.9725.78±8.760.0360.0120.942 Mean (Gy)12.56±3.8628.5±5.5427.53±5.180.0010.0010.692 Mean (Gy)0.99±1.1121.23±9.1419.90±9.060.0010.0010.747Left Main Coronary Artery Max (Gy)11.86±12.8935.25±11.433.51±11.690.0010.0010.740 Mean (Gy)0.36±0.5917.57±5.7615.08±8.180.0010.0010.441Left Anterior Descending Artery Max (Gy)5.37±8.6531.4±3.6326.86±4.780.0010.0010.028Pericardium Mean (Gy)13.49±1.7826.03±5.1224.76±4.220.0010.0010.552 Max (Gy)52.64±1.3153.38±0.4555.3±2.020.1180.0030.015Left Ventricle Mean (Gy)13.86±6.6130.28±5.5827.31±5.560.0010.0010.250 Max (Gy)51.43±0.8852.33±0.8250.6±10.590.0290.8080.613Lung V5 (Gy)21.4±10.3246.93±17.6134.12±13.860.0010.0320.087 V20 (Gy)15.46±6.5416.19±5.7822.1±10.80.7940.1140.144 Mean (Gy)6.03±2.589.45±3.179.38±4.040.0160.0400.966 Open table in a new tab