MP03-06 PROSPECTIVE STUDY ON FDG-PET/CT FOR ON-TREATMENT ASSESSMENT OF RESPONSE TO NEOADJUVANT OR INDUCTION CHEMOTHERAPY IN INVASIVE BLADDER CANCER

Abstract

You have accessJournal of UrologyCME1 May 2022MP03-06 PROSPECTIVE STUDY ON FDG-PET/CT FOR ON-TREATMENT ASSESSMENT OF RESPONSE TO NEOADJUVANT OR INDUCTION CHEMOTHERAPY IN INVASIVE BLADDER CANCER Sarah Einerhand, Charlotte Voskuilen, Elies Fransen van de Putte, Maarten Donswijk, Annemarie Bruining, Michiel Van der Heijden, Laura Mertens, Kees Hendricksen, Erik Vegt, and Bas van Rhijn Sarah EinerhandSarah Einerhand More articles by this author , Charlotte VoskuilenCharlotte Voskuilen More articles by this author , Elies Fransen van de PutteElies Fransen van de Putte More articles by this author , Maarten DonswijkMaarten Donswijk More articles by this author , Annemarie BruiningAnnemarie Bruining More articles by this author , Michiel Van der HeijdenMichiel Van der Heijden More articles by this author , Laura MertensLaura Mertens More articles by this author , Kees HendricksenKees Hendricksen More articles by this author , Erik VegtErik Vegt More articles by this author , and Bas van RhijnBas van Rhijn More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002515.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Neoadjuvant/induction chemotherapy (NAIC) for muscle-invasive bladder carcinoma (MIBC) has been shown to improve survival. On-treatment response assessment aims to detect chemo-(in)sensitive tumors to continue or cease NAIC. We compared accuracy of FDG-PET/CT to contrast-enhanced CT (CECT) for on-treatment assessment of response to NAIC. METHODS: We prospectively included 83 patients with MIBC in 2014-2018 (study protocol: X14BSB). Patients staged as (high-risk) cT2-4N0M0 or cT1-4N+M0-1a were eligible for neoadjuvant (n=40; 48%) or induction (n=43; 52%) chemotherapy, respectively. Response was assessed after 2-3 cycles with FDG-PET/CT (n=83) and CECT (n=60; 72%). FDG-PET/CT images were assessed by 2 nuclear medicine physicians (Peter Mac criteria). CECT images were assessed by 1 radiologist (RECIST1.1 criteria). We assessed prediction of complete pathological response (pCR; ypT0N0), complete pathological downstaging (pCD; ≤ypT1/is/1N0), any downstaging from baseline (ypTN<cTN) and progression (inoperable tumor/ypN+/M+). The reference standard was histopathological assessment or clinical follow-up. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated. RESULTS: In this cohort, pathological response rates were 21% for pCR, 29% for pCD, 49% for any downstaging, and 10% progressed. All diagnostic parameters for FDG-PET/CT and CECT are shown in Table 1. Accuracy of FDG-PET/CT for prediction of pCR, pCD, any downstaging and progression were 74%, 54%, 61% and 83%, respectively. Accuracy of CECT for prediction of pCR, pCD, any downstaging and progression were 78%, 63%, 68% and 77%, respectively. Specificity of CECT was significantly higher than FDG-PET/CT for prediction of any downstaging (59% vs 32%; p=0.022). In all other analyses, there were no significant differences between FDG-PET/CT and CECT (Table 1). CONCLUSIONS: FDG-PET/CT was not more accurate than CECT for assessment of response to NAIC. However, neither were highly accurate and response was often overestimated. Our results suggest more accurate methods for on-treatment response assessment are needed to accurately select patients for continued treatment with NAIC and surgery. Source of Funding: None © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e21 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sarah Einerhand More articles by this author Charlotte Voskuilen More articles by this author Elies Fransen van de Putte More articles by this author Maarten Donswijk More articles by this author Annemarie Bruining More articles by this author Michiel Van der Heijden More articles by this author Laura Mertens More articles by this author Kees Hendricksen More articles by this author Erik Vegt More articles by this author Bas van Rhijn More articles by this author Expand All Advertisement PDF DownloadLoading ...