Factors Predicting Discordance between Clinical and Surgical-Pathologic Staging in Operable Non-Small Cell Lung Cancer

Accurate clinical staging is of the utmost importance for the optimal management of patients with non-small cell lung cancer (NSCLC). The aim of this study was to identify factors associated with discordance between clinical and pathologic staging in patients with operable NSCLC. The medical records of 85 patients with early-stage NSCLC, who had been submitted to thoracotomy followed by surgical resection of the primary tumor and systematic lymph node dissection, were retrospectively reviewed. All patients were staged according to the 7th edition of the TNM staging system. The presence of postoperative upstaging or downstaging was correlated with various demographic and clinicopathological factors, including age, sex, smoking history, tumor histology, tumor size and location. Discordance between clinical and surgical-pathologic staging was found in 45/85 cases (52.9%), and the majority of these patients were upstaged (35/85 cases, 41.2%). Patients with IIB and IB clinical stage had the highest (77.8%) and lowest (48.1%) probability of discordance, respectively. With regard to T stage, disagreement between clinical and surgical-pathologic T stage was noted in 22/85 patients (25.9%), including 16 upstaged patients (16/85, 18.8%) and 6 downstaged patients (6/85, 7.1%). Nodal status was altered postoperatively in 39/85 cases (45.9%), including 29 upstaged patients (29/85, 34.1%) and 10 downstaged patients (10/85, 11.8%). The rate of unsuspected mediastinal lymph node involvement (pathologic stage N2) was 14.1% (12/85 patients), despite negative mediastinoscopy findings. Age was the only statistically significant factor independently associated with staging discordance (odds ratio 0.93; 95% confidence interval, 0.87 to 0.99). Postoperative upstaging or downstaging was observed in a relatively high percentage of our patient population, and was significantly and independently correlated with patient’s age. These observations warrant confirmation in larger prospective series of patients with early-stage NSCLC.