Radiation Therapy Oncology Group consensus panel guidelines for the delineation of the clinical target volume in the postoperative treatment of pancreatic head cancer

Abstract

Purpose: To develop contouring guidelines to be used in the Radiation Therapy Oncology Group protocol 0848, a Phase III randomized trial evaluating the benefit of adjuvant chemoradiation in patients with resected head of pancreas cancer.

Methods and materials: A consensus committee of six radiation oncologists with expertise in gastrointestinal radiotherapy developed stepwise contouring guidelines and an atlas for the delineation of the clinical target volume (CTV) in the postoperative treatment of pancreas cancer, based on identifiable regions of interest and margin expansions. Areas at risk for subclinical disease to be included in the CTV were defined, including nodal regions, anastomoses, and the preoperative primary tumor location. Regions of interest that could be reproducibly contoured on postoperative imaging after a pancreaticoduodenectomy were identified. Standardized expansion margins to encompass areas at risk were developed after multiple iterations to determine the optimal margin expansions.

Results: New contouring recommendations based on CT anatomy were established. Written guidelines for the delineation of the postoperative CTV and normal tissues, as well as a Web-based atlas, were developed.

Conclusions: The postoperative abdomen has been a difficult area for effective radiotherapy. These new guidelines will help physicians create fields that better encompass areas at risk and minimize dose to normal tissues.

Copyright © 2012 Elsevier Inc. All rights reserved.

Figures

Fig. 1

Radiation Therapy Oncology Group protocol 0848 study schema.

Fig. 2

Axial computed tomographic imaging of a patient after pancreaticoduodenectomy, demonstrating the regions of interest outlined in the contouring guidelines: portal vein (PV), pancreaticojejunostomy (PJ), aorta, superior mesenteric artery (SMA), celiac artery (CA), and the tumor bed.

Fig. 3

Axial computed tomographic imaging demonstrating the margin expansions on the regions of interest (ROI) and the final clinical target volume/planning target volume (CTV/PTV).

Fig. 4

Coronal and sagittal views of the clinical target volume and planning target volume.

Fig. 5

Axial computed tomographic imaging of delineation of normal organs at risk.