Planning benchmark study for SBRT for lung and liver tumors


Study PI:

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

Lotte Wilke
University Hospital Zürich
lotte.wilke@usz.ch

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

Study design:

● multi-center, multi-platform bench mark study

Study objectives:

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

Project status:

● Data collection completed
● 1 manuscript accepted, 2 manuscripts in preparation

Major findings and results:

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. Strahlenther Onkol. 2017 May 31.

  • 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 et al, Kann mit einer Normierung auf den Mittelwert im ITV bei Lungen SBRT eine einheitliche Dosisverteilung im Zielvolumen erreicht werden?
Vortrag DEGRO Jahrestagung 2017

  • 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

Moustakis et al, Liver SBRT Bench Mark Study
In collaboration with the DGMP Working Group “Physics and Technology in der Stereotactic Radiotherapy"
Oral Presentation, DEGRO Annual Meeting 2018

  • 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

Data acquisition is finished, manuscript in preparation