Foley et al [8] also reported sensitivity, specificity, and accuracy of FDG-PET/CT of 77.3%, 75%, and 90.9%, respectively, for nodal involvement in a prospective study of 112 patients with esophageal cancer. Given that 82% of lymph node metastases were <6 mm in this study, the authors concluded that imaging staging for N disease was poor. Bunting et al [10] prospectively evaluated 133 patients with esophageal cancer undergoing surgery and reported an N stage accuracy of 78.6% for FDG-PET/CT. Bunting et al [10] also concluded that staging accuracy with respect to the threshold for treatment for neoadjuvant chemoradiation was poor and could lead to over- and undertreatment. A meta-analysis by van Westreenen et al [15] reported pooled sensitivity of 51% and specificity of 84% for FDG-PET/CT for locoregional metastases. Limited performance of FDG-PET/CT in locoregional staging is likely due to poor spatial resolution of PET and the reality that metastatic lymph nodes in esophageal cancer are often small. Even some primary tumors may not be detected with FDG-PET/CT either because of small size or in histologic subtypes with low FDG uptake [2]. There are many studies that have evaluated the use of FDG-PET/CT in detecting M disease in initial staging. Heeren et al [11] investigated 74 patients with FDG-PET/CT and found that FDG-PET/CT increased detection of M1 disease from 37% to 78% in comparison with CT/esophageal US. Vyas et al [16] prospectively investigated 114 patients with biopsy-proven esophageal adenocarcinoma and reported a sensitivity of 57.14% and specificity of 84.53% in detecting metastatic disease. A larger meta-analysis by van Westreenen et al [15] reported a pooled sensitivity and specificity for FDG-PET/CT of 67% and 97%, respectively, in the detection of M1 disease in esophageal cancer.
Staging and Follow up of Esophageal Cancer. Foley et al [8] also reported sensitivity, specificity, and accuracy of FDG-PET/CT of 77.3%, 75%, and 90.9%, respectively, for nodal involvement in a prospective study of 112 patients with esophageal cancer. Given that 82% of lymph node metastases were <6 mm in this study, the authors concluded that imaging staging for N disease was poor. Bunting et al [10] prospectively evaluated 133 patients with esophageal cancer undergoing surgery and reported an N stage accuracy of 78.6% for FDG-PET/CT. Bunting et al [10] also concluded that staging accuracy with respect to the threshold for treatment for neoadjuvant chemoradiation was poor and could lead to over- and undertreatment. A meta-analysis by van Westreenen et al [15] reported pooled sensitivity of 51% and specificity of 84% for FDG-PET/CT for locoregional metastases. Limited performance of FDG-PET/CT in locoregional staging is likely due to poor spatial resolution of PET and the reality that metastatic lymph nodes in esophageal cancer are often small. Even some primary tumors may not be detected with FDG-PET/CT either because of small size or in histologic subtypes with low FDG uptake [2]. There are many studies that have evaluated the use of FDG-PET/CT in detecting M disease in initial staging. Heeren et al [11] investigated 74 patients with FDG-PET/CT and found that FDG-PET/CT increased detection of M1 disease from 37% to 78% in comparison with CT/esophageal US. Vyas et al [16] prospectively investigated 114 patients with biopsy-proven esophageal adenocarcinoma and reported a sensitivity of 57.14% and specificity of 84.53% in detecting metastatic disease. A larger meta-analysis by van Westreenen et al [15] reported a pooled sensitivity and specificity for FDG-PET/CT of 67% and 97%, respectively, in the detection of M1 disease in esophageal cancer.