Planning benchmark study for SBRT for lung, liver and pancreas tumors


Study PI:

Christos Moustakis
Uni-Klinikum Münster
Christos.Moustakis@ukmuenster.de

Stephanie Tanadini-Lang, Lotte Wilke
University Hospital Zürich
stephanie.tanadini-lang@usz.ch

Study design:

● multi-center, multi-platform bench mark study

Study objectives:

  • To harmonize treatment planning reporting and quality for lung SBRT based on the published guidelines of the DEGRO AG Stereotaxie
  • To harmonize treatment planning reporting and quality for liver SBRT based on the published guidelines of the DEGRO AG Stereotaxie
  • To harmonize treatment planning reporting and quality for pancreas SBRT based on the published guidelines of the DEGRO AG Stereotaxie
  • To harmonize treatment planning based on  a mean ITV/GTV dose prescription

Project status:

● Data collection completed
● 3 manuscripts published, 1 manuscript in preparation

Major findings and results:

Moustakis C, Blanck O, Chan MKH, et al. Planning Benchmark Study for Stereotactic Body Radiation Therapy of Liver Metastases: Results of the DEGRO/DGMP Working Group on Stereotactic Radiation Therapy and Radiosurgery. Int J Radiat Oncol Biol Phys. 2022; 113(1):214-227. https://pubmed.ncbi.nlm.nih.gov/35074434/

  • 3 typical Liver SBRT cases
  • 35 participating institutions and 132 generated plans
  • SBRT treatment planning with 3×20Gy prescribed to the mean GTV dose
  • Further objectives and constraints for GTV, PTV and OAR were provided
  • Constraints could not always be fulfilled and trade-offs significantly varied between institutions
  • Five different methods of prescription were compared for a total of 660 plans
  • The mean GTV dose prescription resulted in the least difference for all parameters evaluated

Moustakis C, Blanck O, Ebrahimi Tazehmahalleh F, et al. Planning benchmark study for SBRT of early stage NSCLC : Results of the DEGRO Working Group Stereotactic Radiotherapy. https://pubmed.ncbi.nlm.nih.gov/28567503/

  • 3 typical cases, 22 institutions, 87 plans, 3 x 15 Gy @ 65% isodose
  • PTV dose coverage and simultaneously OARs doses were kept within the clinical limits published in the DEGRO AG guidelines and homogenization of SBRT practice was possible based on the guidelines
  • However, detailed treatment plan characteristics still varied between techniques and institutions and further standardization is warranted, mainly in respect to the mean PTV and GTV dose.
  • Regardless, the ALARA principle should always be applied to optimize treatment planning
  • In summary, all treatment techniques, with all their known advantages and disadvantages, are well suited for SBRT of early stage NSCLC according to the DEGRO AG guidelines.

Wilke L, Moustakis C, Blanck O, et al. Improving interinstitutional and intertechnology consistency of pulmonary SBRT by dose prescription to the mean internal target volume dose. Strahlenther Onkol. 2021; 197(9):836-846. https://pubmed.ncbi.nlm.nih.gov/34196725/

  • 2 typical lung SBRT cases, same ones as in the last study
  • 27 participating institutions, 57 plans
  • SBRT treatment planning with 3x21.5Gy on the mean ITV dose
  • A set on further constraints on PTV, ITV and OAR was provided
  • Constraints could mostly be fulfilled
  • Mean PTV dose differs only by maximally 1.5Gy between the techniques (compared to more than 5 Gy in previous study)
  • In summary, difference between different treatment techniques could be homogenized by prescribing on the mean ITV dose
  • Data acquisition finished, manuscript in preparation