Elsevier

Radiotherapy and Oncology

Volume 118, Issue 1, January 2016, Pages 35-42
Radiotherapy and Oncology

ESTRO-ACROP guidelines: Gliobastoma
ESTRO-ACROP guideline “target delineation of glioblastomas”

https://doi.org/10.1016/j.radonc.2015.12.003 Get rights and content

Abstract

Background and purpose

Target delineation in glioblastoma (GBM) varies substantially between different institutions and several consensus statements are available. This guideline aims to develop a joint European consensus on the delineation of the clinical target volume in patients with a glioblastoma (GBM).

Material and methods

A literature search was conducted in PubMed that evaluated adults with GBM. Both MeSH terms and text words were used and the following search strategy was applied: (“Glioblastoma/radiotherapy” [MeSH] OR “glioblastoma” OR “malignant glioma” OR high-grade glioma) AND ((delineation) OR (target volume) OR (CTV) OR (PTV) OR (margin) OR (recurrence pattern) OR (contouring) OR (organs at risk)). In parallel, abstracts from ESTRO and ASTRO 2010–2015 were analysed and separately reviewed. The ACROP committee identified 14 European experts in close interaction with the ESTRO clinical committee who discussed and analysed the body of evidence concerning GBM target delineation.

Results

Several key issues were identified and are discussed including (i) pre-treatment steps and immobilization, (ii) target delineation and the use of standard and novel imaging techniques, and (iii) technical aspects of treatment including planning techniques, and fractionation. Based on the EORTC recommendation focusing on the resection cavity and residual enhancing regions on T1-sequences with the addition of a 20 mm margin, special situations are presented with corresponding potential adaptations depending on the specific clinical situation.

Conclusions

Currently, based on the EORTC consensus, a single clinical target volume definition based on postoperative T1/T2 FLAIR abnormalities is recommended, using isotropic margins without the need to cone down. A PTV margin based on the individual mask system and IGRT procedures available is advised, usually of the order of 3–5 mm.

Section snippets

Methods and materials

A literature search was conducted in MEDLINE PubMed that evaluated adults with GBM. The search focused on randomised, prospective and retrospective trials published in English (all sample sizes were considered). Both MeSH terms and text words were used and the following search strategy was applied: (”Glioblastoma/radiotherapy” [MeSH] OR “glioblastoma” OR “malignant glioma” OR high-grade glioma) AND ((delineation) OR (target volume) OR (CTV) OR (PTV) OR (margin) OR (recurrence pattern) OR

Preparation

To ensure accurate re-positioning the patient’s head should be immobilized using an individually adapted mask system. Thermoplastic systems are the most widely used and can be prepared at the same appointment as the planning CT scan. A flat position with the head in neutral is the most widely accepted practice as it is most comfortable for the patient. A CT scan should be obtained using 1–3 mm slice thickness from the vertex to the lower border of C3. As GBM can grow rapidly an up-to-date

Conclusions

More accurate and precise target delineation guidelines for GBM should help to promote standardisation and uniformity (see Fig. 1 for a sample case and a flowchart in Fig. 2). Currently, while a number of aspects of the delineation technique are evidence based, many arise from consensus practice.

While recognising that there is a range of approaches to defining the target volume in GBM patients, the ACROP guideline committee proposes the following pragmatic algorithm:

  • Immobilisation with a

Preparation of the guideline

The guideline was prepared following the ESTRO SOP for guidelines and is an expert guideline. The writing committee consisted of the following experts: M.N. coordinated the guideline panel and drafted the manuscript. M.B., A.C., S.E.C., S.C.E., A.F., A.L.G., F.J.L., G.M., R.M., U.R., S.C.S. and D.C.W. were part of the expert panel and participated in the preparation of the manuscript. C.B. initiated the guideline, participated in its conception as well as the preparation of the manuscript. All

Guideline update

This guideline is planned to be updated within a 2 year-time frame unless there are fundamental scientific changes which require an earlier update. Amendments will be made if changes are minor but of clinical significance.

Conflicts of interest

The authors declare that they have no competing interests.

Disclaimer

ESTRO cannot endorse all statements or opinions made on the guidelines. Regardless of the vast professional knowledge and scientific expertise in the field of radiation oncology that ESTRO possesses, the Society cannot inspect all information to determine the truthfulness, accuracy, reliability, completeness or relevancy thereof. Under no circumstances will ESTRO be held liable for any decision taken or acted upon as a result of reliance on the content of the guidelines.

The component

References (50)

  • B.S. Hoppe et al.

    Treatment of nasal cavity and paranasal sinus cancer with modern radiotherapy techniques in the postoperative setting–the MSKCC experience

    Int J Radiat Oncol Biol Phys

    (2007)
  • E.P. Jansen et al.

    Target volumes in radiotherapy for high-grade malignant glioma of the brain

    Radiother Oncol

    (2000)
  • V.S. Jeganathan et al.

    Ocular risks from orbital and periorbital radiation therapy: a critical review

    Int J Radiat Oncol Biol Phys

    (2011)
  • N. Laperriere et al.

    Radiotherapy for newly diagnosed malignant glioma in adults: a systematic review

    Radiother Oncol

    (2002)
  • Y.R. Lawrence et al.

    Radiation dose–volume effects in the brain

    Int J Radiat Oncol Biol Phys

    (2010)
  • S.W. Lee et al.

    Patterns of failure following high-dose 3-D conformal radiotherapy for high-grade astrocytomas: a quantitative dosimetric study

    Int J Radiat Oncol Biol Phys

    (1999)
  • A. Malmstrom et al.

    Temozolomide versus standard 6-week radiotherapy versus hypofractionated radiotherapy in patients older than 60 years with glioblastoma: the Nordic randomised, phase 3 trial

    Lancet Oncol

    (2012)
  • C. Mayo et al.

    Radiation associated brainstem injury

    Int J Radiat Oncol Biol Phys

    (2010)
  • G. Minniti et al.

    Patterns of failure and comparison of different target volume delineations in patients with glioblastoma treated with conformal radiotherapy plus concomitant and adjuvant temozolomide

    Radiother Oncol

    (2010)
  • M. Niyazi et al.

    FET-PET for malignant glioma treatment planning

    Radiother Oncol

    (2011)
  • U. Oppitz et al.

    3D-recurrence-patterns of glioblastomas after CT-planned postoperative irradiation

    Radiother Oncol

    (1999)
  • H.H. Pai et al.

    Hypothalamic/pituitary function following high-dose conformal radiotherapy to the base of skull: demonstration of a dose-effect relationship using dose-volume histogram analysis

    Int J Radiat Oncol Biol Phys

    (2001)
  • C.C. Pan et al.

    Prospective study of inner ear radiation dose and hearing loss in head-and-neck cancer patients

    Int J Radiat Oncol Biol Phys

    (2005)
  • J.T. Parsons et al.

    Radiation retinopathy after external-beam irradiation: analysis of time–dose factors

    Int J Radiat Oncol Biol Phys

    (1994)
  • S. Rieken et al.

    Analysis of FET-PET imaging for target volume definition in patients with gliomas treated with conformal radiotherapy

    Radiother Oncol

    (2013)
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