Diagnostic and prognostic value of FDG PET-CT in patients with suspected recurrent thymic epithelial tumors

This study aimed to evaluate the diagnostic and prognostic value of FDG PET/CT in patients with suspected recurrent thymic epithelial tumors (TETs). We retrospectively reviewed 83 patients with histopathologically proven TETs (50 thymomas; 33 thymic carcinomas) who underwent FDG PET/CT after surgery. The sensitivity and specificity of FDG PET/CT in detecting recurrence were calculated. The progression-free survival rate (PFS) was calculated by the Kaplan-Meier method. FDG PET/CT results were positive in 50 patients and negative in 33. Recurrent TETs were confirmed in 40 of 50 patients with positive PET/CT findings. The sensitivity and specificity of FDG PET/CT were 100% and 76.7%, respectively. Disease progression occurred in 28 patients during the follow-up. FDG PET/CT showed added prognostic value over the Masaoka stage and histopathology. Among patients with the same Masaoka stage, negative PET/CT was significantly associated with better PFS (P < 0.001). Similarly, among patients with the same histopathology, negative PET/CT was also associated with a significantly longer PFS (P < 0.001). FDG PET/CT demonstrated a good diagnostic performance in patients with recurrent TETs and had an important prognostic value in assessing the risk of disease progression.

Automated summary

This study evaluated the diagnostic and prognostic value of FDG PET/CT in patients with suspected recurrent TETs. The results showed that FDG PET/CT had high sensitivity and good specificity in detecting recurrence, and it had important prognostic value in assessing the risk of disease progression.