[18]F-fluoroethyl-l-tyrosine positron emission tomography for radiotherapy target delineation: Results from a Radiation Oncology credentialing program

Nathaniel Barry; Eng-Siew Koh; Martin A Ebert; Alisha Moore; Roslyn J Francis; Pejman Rowshanfarzad; Ghulam Mubashar Hassan; Sweet P Ng; Michael Back; Benjamin Chua; Mark B Pinkham; Andrew Pullar; Claire Phillips; Joseph Sia; Peter Gorayski; Hien Le; Suki Gill; Jeremy Croker; Nicholas Bucknell; Catherine Bettington; Farhan Syed; Kylie Jung; Joe Chang; Andrej Bece; Catherine Clark; Mori Wada; Olivia Cook; Angela Whitehead; Alana Rossi; Andrew Grose; Andrew M Scott

doi:10.1016/j.phro.2024.100568

[18]F-fluoroethyl-l-tyrosine positron emission tomography for radiotherapy target delineation: Results from a Radiation Oncology credentialing program

Phys Imaging Radiat Oncol. 2024 Mar 13:30:100568. doi: 10.1016/j.phro.2024.100568. eCollection 2024 Apr.

Authors

Nathaniel Barry^{1

2}, Eng-Siew Koh³, Martin A Ebert^{1

4

5

2}, Alisha Moore⁶, Roslyn J Francis^{7

5}, Pejman Rowshanfarzad^{1

2}, Ghulam Mubashar Hassan¹, Sweet P Ng⁸, Michael Back⁹, Benjamin Chua¹⁰, Mark B Pinkham¹¹, Andrew Pullar¹¹, Claire Phillips¹², Joseph Sia¹², Peter Gorayski¹³, Hien Le¹³, Suki Gill⁴, Jeremy Croker⁴, Nicholas Bucknell⁴, Catherine Bettington¹⁰, Farhan Syed¹⁴, Kylie Jung¹⁴, Joe Chang³, Andrej Bece¹⁵, Catherine Clark¹⁵, Mori Wada⁸, Olivia Cook⁶, Angela Whitehead⁶, Alana Rossi⁶, Andrew Grose⁶, Andrew M Scott^{16

17}

Affiliations

¹ School of Physics, Mathematics and Computing, University of Western Australia, Crawley, WA, Australia.
² Centre for Advanced Technologies in Cancer Research (CATCR), Perth, WA, Australia.
³ South Western Sydney Clinical School, University of New South Wales, Australia.
⁴ Department of Radiation Oncology, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.
⁵ Australian Centre for Quantitative Imaging, Medical School, University of Western Australia, Crawley, WA, Australia.
⁶ Trans Tasman Radiation Oncology Group (TROG) Cancer Research, Newcastle, NSW Australia.
⁷ Department of Nuclear Medicine, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.
⁸ Department of Radiation Oncology, Austin Health, Heidelberg, VIC, Australia.
⁹ Department of Radiation Oncology, Royal North Shore Hospital, Sydney, NSW, Australia.
¹⁰ Department of Radiation Oncology, Royal Brisbane Womens Hospital, Brisbane, QLD, Australia.
¹¹ Department of Radiation Oncology, Princess Alexandra Hospital, Brisbane, QLD, Australia.
¹² Department of Radiation Oncology, Peter MacCallum Cancer Centre, VIC, Australia.
¹³ Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, SA, Australia.
¹⁴ Department of Radiation Oncology, The Canberra Hospital, Canberra, ACT, Australia.
¹⁵ Department of Radiation Oncology, St George Hospital, Kogarah, NSW, Australia.
¹⁶ Department of Molecular Imaging and Therapy, Austin Health, and University of Melbourne, Melbourne, VIC, Australia.
¹⁷ Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine La Trobe University, Melbourne, VIC, Australia.

Abstract

Background and purpose: The [18]F-fluoroethyl-l-tyrosine (FET) PET in Glioblastoma (FIG) study is an Australian prospective, multi-centre trial evaluating FET PET for newly diagnosed glioblastoma management. The Radiation Oncology credentialing program aimed to assess the feasibility in Radiation Oncologist (RO) derivation of standard-of-care target volumes (TV_MR) and hybrid target volumes (TV_MR+FET) incorporating pre-defined FET PET biological tumour volumes (BTVs).

Materials and methods: Central review and analysis of TV_MR and TV_MR+FET was undertaken across three benchmarking cases. BTVs were pre-defined by a sole nuclear medicine expert. Intraclass correlation coefficient (ICC) confidence intervals (CIs) evaluated volume agreement. RO contour spatial and boundary agreement were evaluated (Dice similarity coefficient [DSC], Jaccard index [JAC], overlap volume [OV], Hausdorff distance [HD] and mean absolute surface distance [MASD]). Dose plan generation (one case per site) was assessed.

Results: Data from 19 ROs across 10 trial sites (54 initial submissions, 8 resubmissions requested, 4 conditional passes) was assessed with an initial pass rate of 77.8 %; all resubmissions passed. TV_MR+FET were significantly larger than TV_MR (p < 0.001) for all cases. RO gross tumour volume (GTV) agreement was moderate-to-excellent for GTV_MR (ICC = 0.910; 95 % CI, 0.708-0.997) and good-to-excellent for GTV_MR+FET (ICC = 0.965; 95 % CI, 0.871-0.999). GTV_MR+FET showed greater spatial overlap and boundary agreement compared to GTV_MR. For the clinical target volume (CTV), CTV_MR+FET showed lower average boundary agreement versus CTV_MR (MASD: 1.73 mm vs. 1.61 mm, p = 0.042). All sites passed the planning exercise.

Conclusions: The credentialing program demonstrated feasibility in successful credentialing of 19 ROs across 10 sites, increasing national expertise in TV_MR+FET delineation.

Keywords: Clinical trials; Credentialing; FET PET; Glioblastoma; Treatment planning.