Volumetric modulated arc therapy and concurrent chemotherapy for esophageal cancers: Dosimetric comparison with 3D conformal radiotherapy and early clinical results
Abstract
Purpose: Despite Intensity Modulated Radiotherapy being the standard of care for most sites, 3D conformal radiotherapy (3DCRT) is still more widely used in esophageal cancers. This study compares dosimetric results of volumetric modulated arc therapy (RA) with that of 3DCRT and evaluates early clinical results of the patients treated with RA and chemotherapy.
Materials and Methods: Evaluation of clinical outcomes in 10 patients treated definitively with RA and concurrent chemotherapy for esophageal cancer were included in the study. These patients were retrospectively planned with 3DCRT using antero-posterior portals till 3960cGy followed by obliques to a total dose of 5940cGy. The dose and target in each phase were kept same in both the plans. Dosimetric parameters were compared between the two plans using paired T-test or a Wilcoxon sign-rank based tests of normality on data distribution.
Results: With a minimum follow-up of 4 months, all the patients tolerated the treatment without grade IV toxicities and treatment interruptions. 7 patients had a complete response and 3 had a partial response of which one patient underwent surgery and is disease free. RA resulted in higher conformity to the target compared to 3DCRT (mean conformity index 1.1 vs.1.8 respectively (p=0.002). RA plans significantly spared lung V15 (32%vs.40.2%, p=0.003), V20 (22.7%vs.29.7%, p=0.003), mean lung dose (13.8Gy vs.17.1Gy, p=0.003), heart V30 (46.8%vs.55.2% p=0.002), mean heart dose (24.3Gy vs.28.1Gy, p=0.003), and spinal cord maximum dose (44Gy vs.46.9Gy, p=0.002). The mean V5 and V10 values were similar with either technique.
Conclusion: Irrespective of site of involvement, the RA resulted in better conformity and better sparing of heart, spinal cord and lungs beyond 15Gy. The dosimetric advantage gained with RA may become clinically relevant in reducing cardio-pulmonary complications especially in multimodality setting.
Downloads
References
Herskovic A, Martz K, al-Sarraf M, et al. Combined chemotherapy and radiotherapy compared with radiotherapy alone in patients with cancer of the esophagus. N Engl J Med. 1992 Jun 11; 326(24):1593-8. DOI: https://doi.org/10.1056/NEJM199206113262403.
Minsky BD, Pajak TF, Ginsberg RJ, et al. INT 0123 (Radiation Therapy Oncology Group 94-05) phase III trial of combined-modality therapy for esophageal cancer: high-dose versus standard-dose radiation therapy. J Clin Oncol. 2002 Mar 1; 20(5):1167-74. DOI: https://doi.org/10.1200/JCO.2002.20.5.1167.
al-Sarraf M, Martz K, Herskovic A, et al. Progress report of combined chemoradiotherapy versus radiotherapy alone in patients with esophageal cancer: an intergroup study. J Clin Oncol. 1997 Jan;15(1):277-84. DOI: https://doi.org/10.1200/JCO.1997.15.2.866.
Vanetti E, Clivio A, Nicolini G, et al. Volumetric modulated arc radiotherapy for carcinomas of the oro-pharynx, hypo-pharynx and larynx: a treatment planning comparison with fixed field IMRT. Radiother Oncol. 2009 Jul;92(1):111-7. doi: https://doi.org/10.1016/j.radonc.2008.12.008. Epub 2009 Jan 20.
Clivio A, Fogliata A, Franzetti-Pellanda A, et al. Volumetric-modulated arc radiotherapy for carcinomas of the anal canal: A treatment planning comparison with fixed field IMRT. Radiother Oncol. 2009 Jul;92(1):118-24. doi: https://doi.org/10.1016/j.radonc.2008.12.020. Epub 2009 Jan 30.
Cozzi L, Dinshaw KA, Shrivastava SK, et al. A treatment planning study comparing volumetric arc modulation with RapidArc and fixed field IMRT for cervix uteri radiotherapy. Radiother Oncol. 2008 Nov;89(2):180-91. doi: https://doi.org/10.1016/j.radonc.2008.06.013. Epub 2008 Aug 8.
Panet-Raymond V, Ansbacher W, Zavgorodni S, et al. Coplanar versus noncoplanar intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) treatment planning for fronto-temporal high-grade glioma. J Appl Clin Med Phys. 2012 Jul 5;13(4):3826. doi: https://doi.org/10.1120/jacmp.v13i4.3826.
Sai Subramanian, Chilukuri Srinivas, K. Ramalingam et al. Volumetric Modulated Arc–Based Hypofractionated Stereotactic Radiotherapy for the Treatment of Selected Intracranial Arteriovenous Malformations: Dosimetric Report and Early Clinical Experience. 2012;83(3):1278-84. DOI: https://doi.org/10.1016/j.ijrobp.2011.02.005.
Chilukuri S, Subramaniam VS, Arun G, et al. Assessing the Feasibility of using Volumetric Modulated Arc Therapy Technology to Increase the Throughput and Quality of Radiotherapy in Developing Countries. Int J Radiat Oncol Biol Phys 2011;78:S568.
Chapet O, Kong FM, Quint LE, et al. CT-based definition of thoracic lymph node stations: an atlas from the University of Michigan. Int J Radiat Oncol Biol Phys. 2005 Sep 1;63(1):170-8.
Fu WH, Wang LH, Zhou MZ, et al. Comparison of conformal and intensity-modulated techniques for simultaneous integrated boost radiotherapy of upper esophageal carcinoma. World J Gastroenterol 2004;10:1098-1102.
Chen YJ, Kernstine KH, Shibata S, et al. Image-guided radiotherapy of esophageal cancer by helical tomotherapy: Acute toxicity and preliminary clinical outcome. J Thoracic Dis 2009;1:11-16.
Nutting CM, Bedford JL, Cosgrove VP, et al. A comparison of conformal and intensity-modulated techniques for oesophageal radiotherapy. Radiother Oncol. 2001 Nov;61(2):157-63.
Wu VW, Sham JS, Kwong DL. Inverse planning in three-dimensional conformal and intensity-modulated radiotherapy of mid-thoracic oesophageal cancer. Br J Radiol. 2004 Jul;77(919):568-72.
Chandra A, Guerrero TM, Liu HH, et al. Feasibility of using intensity-modulated radiotherapy to improve lung sparing in treatment planning for distal esophageal cancer. Radiother Oncol. 2005 Dec;77(3):247-53. Epub 2005 Nov 17. DOI: https://doi.org/10.1016/j.radonc.2005.10.017.
Wang SL, Liao Z, Liu H et al. Intensity-modulated radiation therapy with concurrent chemotherapy for locally advanced cervical and upper thoracic esophageal cancer. World J Gastroenterol 2006;12:5501-5508.
Fenkell L, Kaminsky I, Breen S, et al. Dosimetric comparison of IMRT vs. 3D conformal radiotherapy in the treatment of cancer of the cervical esophagus. Radiother Oncol. 2008 Dec;89(3):287-91. doi: https://doi.org/10.1016/j.radonc.2008.08.008. Epub 2008 Sep 12.
Chen YJ, Liu A, Han C, Helical tomotherapy for radiotherapy in esophageal cancer: a preferred plan with better conformal target coverage and more homogeneous dose distribution. Med Dosim. 2007 Fall;32(3):166-71. DOI: https://doi.org/10.1016/j.meddos.2006.12.003.
Hsu FM, Lee YC, Lee JM, et al. Association of clinical and dosimetric factors with postoperative pulmonary complications in esophageal cancer patients receiving intensity-modulated radiation therapy and concurrent chemotherapy followed by thoracic esophagectomy. Ann Surg Oncol. 2009 Jun;16(6):1669-77. doi: https://doi.org/10.1245/s10434-009-0401-0. Epub 2009 Mar 7.
YapJ C, MalhotraH K, Yang GY. Intensity modulated radiation therapy in the treatment of esophageal cancer. Thoracic Cancer 2010;1: 62-69.
Van Benthuysen L, Hales L, Podgorsak MB. Volumetric modulated arc therapy vs IMRT for the treatment of distal esophageal cancer. Med. Dosim. 2011. Article in press.
MarksL B, Bentzen S M, DeasyJ O, et al. Radiation Dose–Volume Effects in the Lung. Int J Radiat Oncol Biol Phys 2010; 76:S70-76.
OAI - Open Archives Initiative
