Role of positron emission tomography in the (re-)staging of oesophageal cancer

Background. Various studies have demonstrated that 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET), measuring altered tissue glucose metabolism, is a promising non-invasive method for detecting both distant nodal and haematogenous metastases in patients with oesophageal carcinoma (OC) and might thus prevent futile oesophagectomies. Moreover, FDG-PET is a promising tool in assessing response to non-surgical treatment, and might therefore be used for an early decision on whether treatment should be stopped or continued. Material and methos. Review of the recent literature regarding the diagnostic performance of FDG-PET in the preoperative staging of patients with OC and regarding diagnostic accuracy of FDG-PET in assessing response to neoadjuvant therapy in patients with OC compared to conventional techniques (especially computed tomography (CT) and endoscopic ultrasonography (EUS)). Results. A search of the literature resulted in the inclusion of 16 studies on the diagnostic value of FDG-PET. Sensitivity and specificity for the detection of locoregional metastases were moderate. Sensitivity and specificity were reasonable for distant metastases. The diagnostic accuracy of FDG-PET in assessing response to treatment was similar to the accuracy of EUS, but significantly higher than that of CT. Conclusions. The staging value of FDG-PET in OC patients is limited in the detection of locoregional metastases; however; its value is higher in the detection of distant lymphatic and haematogenous metastases. Moreover, FDG-PET is a valuable tool for the non-invasive assessment of histopathologic tumour response after neoadjuvant therapy.