Utility of PET/CT for mediastinal staging of non-small cell lung cancer in stage III (N2)

Abstract

Purpose

To evaluate the accuracy of integrated positron emission tomography with ¹⁸F-fluoro-2-deoxy-d-glucose (FDG) and computed tomography (PET/CT) in mediastinal lymph node staging in patients with potentially operable (N2) non-small cell lung cancer (NSCLC) and to ascertain the role of invasive staging in verifying positron emission tomography (PET)/computed tomography (CT) results.

Material and methods

A retrospective study of consecutive patients with pathologically-proven NSCLC and N2 staging by enhanced CT was performed. A PET/CT scan was performed for all the patients. Lymph node staging was pathologically confirmed when it was possible or by consensus in the Thoracic Cancer Committee. Sensitivity, specificity, negative predictive value and positive predictive value of PET/CT in N2 cases were determined.

Results

A total of 34 patients with N2 by CT were evaluated. PET/CT showed N2 in 30 patients. Discrepancies were found in four patients, two patients were classified as N1 in PET/CT and two patients as N0. Lymph node staging was pathologically confirmed in 20 patients. No false positives were found in PET/CT study. Sensitivity was 94.7%, specificity and positive predictive values were 100% and negative predictive value was 50%.

Conclusions

Our data show that integrated PET/CT provides high sensitivity and positive predictive value in mediastinal nodal staging of NSCLC patients. Therefore, in patients with potentially resectable lung cancer, neoadjuvant chemotherapy candidate, mediastinoscopy could be reserved for restaging after induction therapy.