Optimal gross tumor volume definition in lung-sparing intensity modulated radiotherapy for pleural mesothelioma: an in silico study

Authors

  • Angela Botticella Department of Oncology, Experimental Radiation Oncology, KU Leuven–University of Leuven, Leuven, Belgium
  • Gilles Defraene Department of Oncology, Experimental Radiation Oncology, KU Leuven–University of Leuven, Leuven, Belgium
  • Kristiaan Nackaerts Respiratory Diseases/Respiratory Oncology Unit, KU Leuven–University of Leuven, University Hospitals Leuven, Leuven, Belgium
  • Christophe M. Deroose Department Imaging and Pathology, Nuclear Medicine and Molecular Imaging, KU Leuven–University of Leuven, University Hospitals Leuven, Leuven, Belgium
  • Johan Coolen Radiology Department, University Hospitals Leuven, Leuven, Belgium
  • Philippe Nafteux Department of Thoracic Surgery, University Hospitals Leuven, Leuven, Belgium
  • Stephanie Peeters Department of Radiation Oncology, KU Leuven–University of Leuven, University Hospitals Leuven, Leuven, Belgium
  • Umberto Ricardi Department of Oncology, Radiation Oncology, University of Turin, Turin, Italy
  • Dirk De Ruysscher Department of Radiation Oncology, KU Leuven–University of Leuven, University Hospitals Leuven, Leuven, Belgium; ;GROW–School for Oncology and Developmental Biology, Department of Radiation Oncology (MAASTRO clinic), Maastricht University Medical Center, Maastricht, The Netherlands

DOI:

https://doi.org/10.1080/0284186X.2016.1234066

Abstract

Background: The gross tumor volume (GTV) definition for malignant pleural mesothelioma (MPM) is ill-defined. We therefore investigated which imaging modality is optimal: computed tomography (CT) with intravenous contrast (IVC), positron emission tomography-CT (PET/CT) or magnetic resonance imaging (MRI).

Material and methods: Sixteen consecutive patients with untreated stage I–IV MPM were included. Patients with prior pleurodesis were excluded. CT with IVC, 18FDG-PET/CT and MRI (T2 and contrast-enhanced T1) were obtained. CT was rigidly co-registered with PET/CT and with MRI. Three sets of pleural GTVs were defined: GTVCT, GTVCT+PET/CT and GTVCT+MRI. Quantitative and qualitative evaluations of the contoured GTVs were performed.

Results: Compared to CT-based GTV definition, PET/CT identified additional tumor sites (defined as either separate nodules or greater extent of a known tumor) in 12/16 patients. Compared to either CT or PET/CT, MRI identified additional tumor sites in 15/16 patients (p = .7). The mean GTVCT, GTVCT+PET/CT and GTVCT+MRI [±standard deviation (SD)] were 630.1 cm3 (±302.81), 640.23 cm3 (±302.83) and 660.8 cm3 (±290.8), respectively. Differences in mean volumes were not significant. The mean Jaccard Index was significantly lower in MRI-based contours versus all the others.

Conclusion: As MRI identified additional pleural disease sites in the majority of patients, it may play a role in optimal target volume definition.

Downloads

Download data is not yet available.

Downloads

Additional Files

Published

2016-12-01

How to Cite

Botticella, A., Defraene, G., Nackaerts, K., Deroose, C. M., Coolen, J., Nafteux, P., … De Ruysscher, D. (2016). Optimal gross tumor volume definition in lung-sparing intensity modulated radiotherapy for pleural mesothelioma: an in silico study. Acta Oncologica, 55(12), 1450–1455. https://doi.org/10.1080/0284186X.2016.1234066

Issue

Vol. 55 No. 12 (2016): Acta Oncologica

Section

Articles