Comparison between fluorine-18 fluorodeoxyglucose PET/CT (PET) and contrast enhancement Computed Tomography (ceCT) for staging in esophageal cancer

Objectives to evaluate the role of PET for staging in esophageal cancer and further to compare this method with ceCT

Methods Seventy-eight patients underwent PET before surgical esophagectomy and LN dissection to identify primary lesion but, in particular, LN pathological uptake. PET’s LN involvement was compared with the histopathologic results to investigate the diagnostic accuracy of PET for tumor staging. In addition, we examined the correlation between the diagnostic accuracy of PET for LN involvement and the (18)F-FDG avidity of the primary lesions, to observe a potential correlation between tumor aggressiveness and LN metastasis. Diagnostic data were correlated with pathologic findings

Results The diagnostic accuracy of PET for LN metastasis showed a sensitivity ranging from 43.4% to 75.6%, whereas the specificity was higher than 92.1% both in thoracic and abdominal LN. Uptake of FDG in the primary tumor was found in 43 (55.1%) cases. Comparison of FDG uptake and clinicopathologic findings showed a significant correlation between (18)F-FDG uptake of the primary lesions and metastatic LNs in the thoracic field (R = 0.56, p<0.05). The survival rate in cases with high FDG uptake (SUV >3) was significantly lower than that in cases with low FDG uptake (SUV < 3; p<0.05). In the evaluation of LN staging by the detection of LN metastasis, PET and ceCT showed, respectively a sensitivity, specificity and accuracy of 77.8%, 92.9%, 84.4% and 61.1%, 71.4%, and 65.6%. PET showed a high accuracy in the neck, upper thoracic, and abdominal regions. However, in the mid- and lower thoracic regions, the sensitivity was low

Conclusions PET may be used as a non invasive diagnostic technique in assessing the aggressiveness and prognosis in patients with esophageal cancer. The sensitivity, specificity, and accuracy of lymph node staging is higher with PET than ceCT imaging. PET gives useful information to guide the choice of treatment of esophageal cancer