Advantages of FDG-PET/CT over CT alone in the preoperative assessment of lymph node metastasis in patients with esophageal cancer.

ABSTRACT

PURPOSE: The aim of this study was to determine the benefits of (18)F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) compared to CT alone in the preoperative assessment of lymph node metastasis in patients with esophageal cancer. METHODS: One-hundred and seven patients who underwent esophagectomy with lymph node dissection between March 2007 and December 2009 were eligible. Sixty-seven patients were treated with surgery alone (SA group), while 40 patients received preoperative treatment prior to surgery (PT group). The pathological results of 1,403 dissected lymph node stations were compared with the results obtained using each imaging modality. RESULTS: PET/CT showed a significantly higher specificity and positive predictive value (PPV) than CT alone (97.7 vs. 94.1 % and 64.6 vs. 44.0 %, respectively), when analyzed by the lymph node stations. The PPV of PET/CT for N1 cases was significantly better than that of CT alone (78.9 vs. 53.9 %), particularly in the PT group (91.3 vs. 65.4 %). Among the patients in the SA group, the number of metastatic nodes was significantly higher in PET-N1 cases than in PET-N0 cases (5.78 vs. 1.90). CONCLUSION: PET/CT is useful for selecting patients with multiple lymph node metastases and also for detecting residual metastatic nodes after PT, and thus is beneficial to decide on the appropriate treatment strategy for patients with esophageal cancer.