Fluorine-18 fluorodeoxyglucose positron emission tomography in the preoperative staging of thoracic oesophageal and gastro-oesophageal junction cancer: a prospective study

Abstract

Background: The pre-operative staging in oesophageal cancer is often challenging and underestimation of the extent of the disease may lead to unnecessary surgery.

Aim: To audit the use and assess the value of fluorine-18 fluorodeoxyglucose positron emission tomography ((18)F FDG-PET) as a staging tool for thoracic oesophageal and gastro-oesophageal junction (GOJ) cancers in our oncological surgical practice.

Patients and methods: Over a 3 year period, between 2002 and 2004, 134 patients with thoracic oesophageal or GOJ cancer were referred to our unit for treatment. The standard preoperative staging investigation in all cases was CT (thorax, abdomen and pelvis). A preoperative FDG-PET scan was further requested in 22 patients. The case notes of all the patients that underwent a FDG-PET scan were reviewed and compared with the preoperative imaging, the operative findings and the histopathology of the resected tumours.

Results: Eighteen men and 4 women with a median age of 65 (range 43-79) years were studied. After FDG-PET, 13 out of 22 patients (59%) were deemed suitable for tumour resection. Twelve of the 13 patients were fit to undergo surgery. At laparotomy, 2 of those (17%) were found inoperable due to widespread disease. The sensitivity of CT versus FDG-PET to detect infiltrated lymph nodes was 29% (95% CI: 3-70) versus 71% (95% CI: 29-96) (P=0.0412), whereas both tests had 67% specificity (95% CI: 9-99) in detecting lymph nodes. The sensitivity and the specificity of CT versus FDG-PET to detect distant organ metastases (M1b) were 33% (95% CI: 4-77) and 88% (95% CI: 47-99) versus 50% (95% CI: 6-93) and 100% (95% CI: 69-100), respectively (P>0.05). The FDG-PET regarding the N and M status differed from the CT in 11 patients and led to modification of the planned management in 5 of them.

Conclusions: FDG-PET is more accurate than CT in defining N and M status. It can result in a reduction of unnecessary surgery in a significant number of patients. The combined PET-CT scan as a single imaging modality is expected to further improve diagnostic accuracy of FDG-PET.