{"id":245484,"date":"2026-10-16T01:43:20","date_gmt":"2026-10-16T06:43:20","guid":{"rendered":"https:\/\/lifeboat.com\/blog\/2026\/10\/volumetric-discordance-between-%c2%b9%e2%81%b8f-fet-pet-mri-and-mri-based-radiotherapy-target-volumes-in-high-grade-glioma-a-prospective-pilot-study-fetsmart"},"modified":"2026-10-16T01:43:20","modified_gmt":"2026-10-16T06:43:20","slug":"volumetric-discordance-between-%c2%b9%e2%81%b8f-fet-pet-mri-and-mri-based-radiotherapy-target-volumes-in-high-grade-glioma-a-prospective-pilot-study-fetsmart","status":"publish","type":"post","link":"https:\/\/lifeboat.com\/blog\/2026\/10\/volumetric-discordance-between-%c2%b9%e2%81%b8f-fet-pet-mri-and-mri-based-radiotherapy-target-volumes-in-high-grade-glioma-a-prospective-pilot-study-fetsmart","title":{"rendered":"Volumetric discordance between \u00b9\u2078F-FET-PET\/MRI and MRI-based radiotherapy target volumes in high-grade glioma: a prospective pilot study (FETSMaRT)"},"content":{"rendered":"<p style=\"padding-right: 20px\"><a class=\"aligncenter blog-photo\" href=\"https:\/\/lifeboat.com\/blog.images\/volumetric-discordance-between-c2b9e281b8f-fet-pet-mri-and-mri-based-radiotherapy-target-volumes-in-high-grade-glioma-a-prospective-pilot-study-fetsmart.jpg\"><\/a><\/p>\n<p>High-grade gliomas carry a poor prognosis, and MRI-based radiotherapy (RT) planning may inadequately capture metabolically active tumor infiltration. \u00b9\u2078F-fluoroethyl-tyrosine (FET) PET provides superior tumor delineation, yet prospective North American evidence supporting integration with RT planning remains limited.<\/p>\n<p>FETSMaRT enrolled 30 patients with WHO grade 3 or 4 high-grade glioma receiving post-operative RT. FET-PET\/MRI was acquired before RT with the radiation oncologist blinded to PET, enabling retrospective quantification of discordance between MRI-based and FET-PET\/MRI-derived gross tumor (GTV), clinical target (CTV), and planning target (PTV) volumes. In the glioblastoma subgroup (<i>n<\/i> = 23), Kaplan\u2013Meier and Cox analyses related GTV and CTV discordance to time to progression.<\/p>\n<p>Median age was 60 years; 77% had glioblastoma and 60% MGMT promoter methylation. GTV discordance occurred in 17\/30 patients (56.7%) and CTV discordance in 15\/30 (50.0%). FET-PET\/MRI-derived volumes significantly exceeded MRI-based volumes for GTV (43.6 vs. 38.6 cc; p 0.0001), CTV (119.2 vs. 110.8 cc; p = 0.0045), and PTV (171.1 vs. 159.6 cc; p = 0.0003). Larger GTV\u2206 and CTV\u2206 change values were associated with numerically shorter median time to progression, but neither association was statistically significant. Radiation treatment failures were predominantly central (60.0%).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>High-grade gliomas carry a poor prognosis, and MRI-based radiotherapy (RT) planning may inadequately capture metabolically active tumor infiltration. \u00b9\u2078F-fluoroethyl-tyrosine (FET) PET provides superior tumor delineation, yet prospective North American evidence supporting integration with RT planning remains limited. FETSMaRT enrolled 30 patients with WHO grade 3 or 4 high-grade glioma receiving post-operative RT. FET-PET\/MRI was acquired [\u2026]<\/p>\n","protected":false},"author":662,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-245484","post","type-post","status-publish","format-standard","hentry","category-biotech-medical"],"_links":{"self":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/245484","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/users\/662"}],"replies":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/comments?post=245484"}],"version-history":[{"count":0,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/245484\/revisions"}],"wp:attachment":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/media?parent=245484"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/categories?post=245484"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/tags?post=245484"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}