Recurrence pattern after [(18)F]Fluoroethyltyrosine-Positron Emission Tomography-guided radiotherapy for high-grade glioma: A prospective study

Weber, Damien C.; Casanova, Nathalie; Zilli, Thomas; Buchegger, Franz; Rouzaud, Michel; Nouet, Philippe; Vees, Hansjorg; Ratib, Osman; Dipasquale, Giovanna; Miralbell, Raymond

doi:10.1016/j.radonc.2009.08.043

« Previous Next »Radiotherapy & Oncology
Volume 93, Issue 3 , Pages 586-592, December 2009

Recurrence pattern after [(18)F]Fluoroethyltyrosine-Positron Emission Tomography-guided radiotherapy for high-grade glioma: A prospective study

Damien C. Weber
- Department of Radiation Oncology, and
- Department of Radiation Oncology, University of Geneva, Switzerland
- Corresponding author. Address: Department of Radiation Oncology, Geneva University Hospital, CH-1211 Geneva 14, Switzerland.
Nathalie Casanova
- Department of Radiation Oncology, and
Thomas Zilli
- Department of Radiation Oncology, and
Franz Buchegger
- Department of Nuclear Medicine, Geneva University Hospital, Switzerland
Michel Rouzaud
- Department of Radiation Oncology, and
Philippe Nouet
- Department of Radiation Oncology, and
Hansjorg Vees
- Department of Radiation Oncology, and
Osman Ratib
- Department of Nuclear Medicine, Geneva University Hospital, Switzerland
- Department of Radiation Oncology, University of Geneva, Switzerland
Giovanna Dipasquale
- Department of Radiation Oncology, and
Raymond Miralbell
- Department of Radiation Oncology, and
- Department of Radiation Oncology, University of Geneva, Switzerland

Received 13 November 2008; received in revised form 21 August 2009; accepted 30 August 2009. published online 27 September 2009.

Abstract

Purpose

To assess the failure pattern observed after ¹⁸F fluoroethyltyrosine (FET) planning after chemo- and radiotherapy (RT) for high-grade glioma.

Methods

All patients underwent prospectively RT planning using morphological gross tumour volumes (GTVs) and biological tumour volumes (BTVs). The post-treatment recurrence tumour volumes (RTVs) of 10 patients were transferred on their CT planning. First, failure patterns were defined in terms of percentage of RTV located outside the GTV and BTV. Second, the location of the RTV with respect to the delivered dose distribution was assessed using the RTV’s DVHs. Recurrences with >95% of their volume within 95% isodose line were considered as central recurrences. Finally, the relationship between survival and GTV/BTV mismatches was assessed.

Results

The median percentages of RTV outside the GTV and BTV were 41.8% (range, 10.5–92.4) and 62.8% (range, 34.2–81.1), respectively. The majority of recurrences (90%) were centrally located. Using a composite target volume planning formalism, the degree of GTV and BTV mismatch did not correlate with survivorship.

Conclusions

The observed failure pattern after FET-PET planning and chemo-RT is primarily central. The target mismatch-survival data suggest that using FET-PET planning may counteract the possibility of BTV-related progression, which may have a detrimental effect on survival.

Keywords: Recurrence pattern, Glioblastoma, FET-PET