Diagnostic accuracy of ¹⁸F-FDG PET/CT for detection of suspected recurrence in patients with oesophageal carcinoma.
Objective: To evaluate the role of (18)F-FDG PET/CT in the detection of recurrence in patients with oesophageal carcinoma, suspected clinically or following conventional investigations.
Methods: This was a retrospective study. Data from 180 patients (age 56.3 ± 10.4 years; 126 men, 54 women) with histopathologically proven oesophageal carcinoma (squamous cell 115, adenocarcinoma 59, neuroendocrine carcinoma 4, small cell 1, poorly differentiated 1) who had undergone 227 (18)F-FDG PET/CT studies for suspected recurrence were analysed. Recurrence was suspected clinically or following conventional investigations. PET/CT images were revaluated by two nuclear medicine physicians in consensus. Findings were grouped into local, nodal and distant recurrence. Results were compared to those from contrast-enhanced (CE) CT when available (109 patients). Clinical/imaging follow-up (minimum 6 months) with histopathology (when available) was taken as the reference standard.
Results: Of the 227 (18)F-FDG PET/CT studies,166 were positive and 61 were negative for recurrent disease. PET/CT showed local recurrence in 134, nodal recurrence in 115 and distant recurrence in 47, with more than one site of recurrence in 34. The PET/CT findings were true-positive in 153 studies, true-negative in 54, false-positive in 13 and false-negative in 7. The sensitivity of (18)F-FDG PET/CT was 96%, the specificity was 81%, the positive and negative predictive values were 92% and 89%, respectively, and the accuracy was 91%. PET/CT showed similar accuracy in patients with squamous cell carcinoma and in those with adenocarcinoma (P = 0.181).(18)F-FDG PET/CT was more specific than CECT (67% vs. 21%; P < 0.0001). PET/CT was superior to CECT for the detection of nodal recurrence (P < 0.0001), but not local recurrence (P = 0.093) or distant metastases (P = 0.441).
Conclusions: (18)F-FDG PET/CT shows high accuracy in the detection of suspected recurrence in patients with oesophageal carcinoma. It is more specific than and is superior to CECT in the detection of nodal recurrence.