Diagnostic value of ¹⁸F‐FDG PET/CT versus diffusion‐weighted MRI in detection of residual or recurrent tumors after definitive (chemo) radiotherapy for laryngeal and hypopharyngeal squamous cell carcinoma: A prospective study

Abstract

BackgroundDespite advances in treatment, residual or recurrent tumors after definitive (chemo) radiotherapy for laryngeal and hypopharyngeal squamous cell carcinoma (SCC) remain a challenge in clinical management and require accurate and timely detection for optimal salvage therapy. This study aimed to compare the diagnostic value of Fluorine 18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) and diffusion‐weighted magnetic resonance imaging (DW‐MRI) in detecting residual or recurrent tumors after definitive (chemo) radiotherapy for laryngeal and hypopharyngeal SCC.MethodsA prospective study was conducted on 30 patients who presented with new symptoms after definitive (chemo) radiotherapy for laryngeal (n = 21) and hypopharyngeal (n = 9) carcinoma. Both 18F‐FDG PET/CT and DW‐MRI were performed and histopathologic analysis served as the standard of reference.ResultsHistopathology showed 20 patients as positive and 10 as negative for tumors. 18F‐FDG PET/CT detected all tumors correctly but was falsely positive in one case. DW‐MRI detected tumors in 18 out of 20 positive patients and correctly excluded tumors in all negative patients. The sensitivity and specificity of 18F‐FDG PET/CT were 100% and 90%, respectively, while the values for DW‐MRI were 90% and 100%, respectively.ConclusionsThe study concludes that 18F‐FDG PET/CT is slightly superior to DW‐MRI in detecting residual or recurrent tumors after definitive (chemo) radiotherapy for laryngeal and hypopharyngeal SCC. The combined use of 18F‐FDG PET/CT and DW‐MRI can potentially improve specificity in therapy response evaluation.