Abstract
Objective
To evaluate the diagnostic performance of fluorine 18 fluorodeoxyglucose positron emission tomography/magnetic resonance imaging (18F-FDG PET/MR) in the preoperative staging of hypopharyngeal cancer (HPC), compare it with conventional enhanced computed tomography (CT) and MR, and further explore the prognostic value of its metabolic and diffusion metrics for HPC.
Methods
This retrospective study included 33 patients with pathologically confirmed HPC. All patients underwent preoperative 18F-FDG PET/MR, CT, and MR examination. The staging performance of the three modalities was evaluated using pathological staging as a reference. Additionally, metabolic indicators and diffusion-related parameters from PET/MR were collected to investigate their impact on larynx preservation and survival.
Results
PET/MR demonstrated accuracies of 90.9% and 71.4% in the preoperative T and N staging, respectively, significantly higher than those of CT (54.5%, P = 0.001; 42.9%, P = 0.021) and MR (66.7%, P = 0.016; 42.9%, P = 0.021). Significant differences were observed in the maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), minimum apparent diffusion coefficient (ADCmin), and mean ADC (ADCmean) across different T stages, and in SUVmax, mean SUV (SUVmean), total lesion glycolysis (TLG), and MTV across different N stages. ADCmin and ADCmean showed good predictive capability for larynx preservation, with AUCs of 0.857 and 0.920 (P < 0.05), respectively. In survival analysis, high ADCmin (P < 0.0001) and high ADCmean (P = 0.0011) were significantly associated with better survival, with AUCs of 0.815 and 0.866 (P < 0.05), respectively.
Conclusion
In HPC, 18F-FDG PET/MR imaging significantly surpasses CT and MR in preoperative diagnostic staging. Its diffusion-related parameters have substantial prognostic value, with high ADC values associated with larynx preservation and favorable survival, serving as prognostic indicators for HPC.