Clinical stage T1-T2N0M0 oesophageal cancer: accuracy of clinical staging and predictive factors for lymph node metastasis

OBJECTIVES The aim of this study was to evaluate the accuracy of clinical staging in patients with clinical stage T1-2N0M0 (cT1-T2N0M0) oesophageal cancer and to assess predictive factors associated with lymph node (LN) metastases in those patients. METHODS From 2005 through 2010, 240 patients were identified with cT1-T2N0M0 oesophageal cancer followed by oesophageal resection without induction therapy. Clinical staging was performed by both endoscopic ultrasound (EUS) and positron-emission tomography (PET) scans. RESULTS The study included 174 patients with cT1N0M0 and 66 patients with cT2N0M0 stage oesophageal cancer. Clinical T stage correlated with pathological T stage in 182 of 240 (76 %) patients: 167 of 174 patients (96 %) for cT1N0 and 15 of 66 patients (23 %) for cT2N0. Nodal metastases occurred in 53 patients (22 %) and the prevalence of nodal disease was 16 % in cT1N0 patients and 39 % in cT2N0 patients. Clinical tumour, nodal, metastasis (TNM) staging accurately predicted pathological TNM staging in 62 % of patients (148 of 240), with an accuracy of 79 % for cT1N0 and 15 % for cT2N0. Among the 62 clinically understaged patients, 53 were pathologically upstaged because of nodal metastases. Significant factors associated with LN metastases on multivariate logistic regression were cT2 stage (odd ratios (ORs): 2.87, 95 % confidence intervals (CIs): 1.44-5.69, P = 0.003), poor differentiation (well/unknown vs poor, OR: 5.51, CI: 1.38-22.00, P = 0.01) and maximum standardized uptake value (SUVmax) > 3.15 (OR: 1.99, 95 % CI: 1.01-3.96, P = 0.047). CONCLUSIONS Clinical staging using both EUS and PET demonstrated high accuracy for predicting cT1N0M0 oesophageal cancer pathological staging, but was inadequate for predicting staging for cT2N0M0 cancer. Clinical factors such as SUVmax and tumour differentiation could help select patients with cT1-T2N0M0 tumours that might be upstaged because of unexpected LN metastases.