Original Research ARTICLE
Dosimetric and radiobiological comparison of external beam radiotherapy using simultaneous integrated boost technique for esophageal cancer in different location
- 1Department of Radiation Oncology, Shandong Cancer Hospital, China
- 2Shandong Cancer Hospital, Shandong University, China
- 3Jining Medical University, China
Objectives: To compare treatment plans of intensity modulated radiotherapy (IMRT), volumetric modulated arc radiotherapy (VMAT) and helical tomotherapy (HT) with simultaneous integrated boost (SIB) technique for esophageal cancer (EC) of different locations using dosimetry and radiobiology.
Methods: 40 EC patients were planned for IMRT, VMAT and HT plans, including 10 cases located in the cervix, upper, middle and lower thorax, respectively. Dose-volume metrics, conformity index (CI), homogeneity index (HI), tumor control probability (TCP) and normal tissue complication probability (NTCP) were analyzed to evaluate treatment plans.
Results: HT showed significant improvement over IMRT and VMAT in terms of CI (p=0.007), HI (p<0.001) and TCP (p<0.001) in cervical EC. IMRT yielded more superior CI, HI and TCP compared with VMAT and HT in upper and middle thoracic EC (all p<0.05). Additionally, V30 (27.72±8.67%), mean dose (1801.47±989.58cGy) and NTCP (Niemierko model: 0.44±0.55%; Lyman-Kutcher-Burman model: 0.61±0.59%) of heart in IMRT were sharply reduced than VMAT and HT in middle thoracic EC. For lower thoracic EC, the three techniques offered similar CI and HI (all p>0.05). But VMAT dramatically lowered liver V30 (9.97±2.84%), and reduced NTCP of lungs (Niemierko model: 0.47±0.48%; Lyman-Kutcher-Burman model: 1.41±1.07%) and liver (Niemierko model: 0.10±0.08%; Lyman-Kutcher-Burman model: 0.17±0.17%).
Conclusions: HT was a good option for cervical EC with complex target coverage but little lungs and heart involvement as it achieved superior dose conformity and uniformity. Due to potentially improving tumor control and reducing heart dose with acceptable lungs sparing, IMRT was a preferred choice for upper and middle thoracic EC with large lungs involvement. VMAT could ameliorate therapeutic ratio and lower lungs and liver toxicity, which was beneficial for lower thoracic EC with little thoracic involvement but being closer to heart and liver. Individually choosing optimal technique for EC in different location will be warranted.
Keywords: esophageal cancer, IMRT, VMAT, HT, Dosimetry, Radiobiology, TCP, NTCP
Received: 26 Apr 2019;
Accepted: 10 Jul 2019.
Edited by:Steven H. Lin, University of Texas MD Anderson Cancer Center, United States
Reviewed by:CHUNHUI HAN, City of Hope National Medical Center, United States
Ruijie Yang, Peking University Third Hospital, China
Bao-Tian Huang, Cancer Hospital of Shantou University Medical College, China
Copyright: © 2019 Wang, Li, Meng, Li, Sun, Shang, Pang, Li, Lu and Yu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Prof. Jie Lu, Shandong Cancer Hospital, Shandong University, Jinan, 250117, Shandong Province, China, email@example.com
Prof. Jinming Yu, Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, 250117, Shandong Province, China, firstname.lastname@example.org