The additional value of PET/CT over PET in FDG imaging of oesophageal cancer

Purpose: The aim of this study was to assess the value of combined PET/CT compared with PET reviewed side-by-side with CT, in patients with oesophageal cancer, before and after surgery. Methods: Forty-one FDG PET/CT studies were performed in 32 patients with oesophageal cancer, before surgery (n=18) or during follow-up after resection of the primary tumour (n=23). One hundred and fifteen sites suspicious for malignancy were evaluated. PET/CT was prospectively compared with PET reviewed side-by-side with CT, for detection, accurate localisation and characterisation of malignant sites. PET/CT performance in different anatomical regions was compared before and after surgery. The impact of fused data on patient management was retrospectively assessed. Results: PET/CT had an incremental value over PET for interpretation of 25 of 115 sites (22%), changing the initial characterisation of ten sites to either malignant (n=1) or benign (n=9), and defining the precise anatomical location of 15 sites. PET/CT provided better specificity and accuracy than PET for detecting sites of oesophageal cancer (81% and 90% vs 59% and 83% respectively, p<0.01). Fusion was of special value for interpretation of cervical and abdomino-pelvic sites, for disease assessment in loco-regional lymph nodes before surgery and in regions of postoperative anatomical distortion. PET/CT had an impact on the further management of four patients (10%), by detecting nodal metastases that warranted disease upstaging (n=2) and by excluding disease in sites of benign uptake after surgery (n=2). Conclusion: PET/CT improves the accuracy of FDG imaging in oesophageal cancer and provides data of diagnostic and therapeutic significance for further patient management.