Integrated Positron-emission Tomography for Nodal Staging in Lung Cancer

As lymph node metastasis is the most important factor determining the surgical outcome of lung cancer, we evaluated the accuracy and clinical usefulness of functional imaging with integrated positron-emission tomography and computed tomography in nodal staging of non-small-cell lung cancer. Between October 2003 and August 2004, 43 newly diagnosed patients underwent curative surgical resection or mediastinoscopic nodal biopsy after chest computed tomography as well as whole-body functional imaging for clinical staging. Based on histopathologic findings in the lymph nodes, we compared the diagnostic usefulness of computed tomography and functional imaging. Twenty-two patients were N0 stage, 6 were N1, 11 were N2, and 4 were N3. Although functional imaging seemed to be superior for evaluation of N2 nodes, there were no significant differences in the sensitivity, specificity, positive-predictive value, negative-predictive value, or accuracy. The situation was similar for N1 nodes, and there were no significant differences except for the false-negative rate. High false-positive and negative-rates for N2 lymph nodes suggest that functional imaging should not replace mediastinoscopy.