Dose Constraints to Prevent Radiation-induced Brachial Plexopathy in Patients Treated for Lung Cancer

Abstract

Purpose-As the recommended radiation dose for non-small cell lung cancer (NSCLC) increases, meeting dose constraints for critical structures like the brachial plexus becomes increasingly challenging, particularly for tumors in the superior sulcus. In this retrospective analysis, we compared dose-volume histogram information with the incidence of plexopathy to establish the maximum tolerated dose to the brachial plexus.Methods and Materials-We identified 90 patients with NSCLC treated with definitive chemoradiation from March 2007 through September 2010 who had received>55 Gy to the brachial plexus. We used a multi-atlas segmentation method combined with deformable image registration to delineate the brachial plexuson the original planning CT scans and scoredplexopathy according to the Common Terminology Criteria for Adverse Events v4.03. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Results-The Meeting Presentations:This work was submitted for presentation at the 53 rd (2011) ASTRO meeting. Conflicts of Interest:The authors declare no conflicts of interest regarding the work presented here. Conclusions-For lung cancers near the apical region, brachial plexopathy is a major concern for high-dose radiation therapy. We developed a computer-assisted image segmentation method which allowed us to rapidly and consistently contour the brachial plexus and establish the dose limits to minimize the risk of brachial plexopathy. Our results could be used as a guideline in future prospective trialswithhigh dose radiation therapy for unresectable lung cancer. NIH Public Access

Organs at risk in lung SBRT

“…Recently Nuyttens et al published data from a dose-escalation study (45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59)(60) Gy in 3-7 fractions) of 56 patients treated by CyberKnife unit. They developed a statistical dose-response model to assess the equivalent uniform dose, D10%, D5cc, D1cc, and Dmax, to the esophagus and the risk of toxicity.…”

“…Limited dosimetric studies for RIBP indicate a threshold effect. Multiple traumas, as those from tumor invasion and/or previous surgery, may reduce the threshold for development of RIBP symptoms [47,48]. Forquer et al [49] recommend the use of regimens contributing with a maximum brachial plexus doses of less than 26 Gy in three to four fractions.…”