The value of [¹⁸F]fluoro-2-deoxy-D-glucose positron emission tomography in the selection of patients with stage IIIA-N2 non-small cell lung cancer for combined modality treatment

Combined modality treatment (CMT) for patients with stage IIIA-N2 non-small cell lung cancer (NSCLC) is at present studied extensively. To select patients with truly stage IIIA-N2 disease, however, proves to be difficult with current diagnostic tests. Distant metastases may become clinically overt during induction chemotherapy (IC) or shortly after, revealing the inaccuracies of current staging algorithms. A prospective study with [¹⁸F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) in IIIA-N2 NSCLC patients was performed to assess its value in the selection of this patient group. Fifty-seven patients received a whole body FDG PET scan as part of an ongoing response monitoring trial. Results were compared with conventional staging. In 32/57 (56%) PET suggested upstaging, which was confirmed in 17/57 (30%) with a median follow-up of 16 (range 2-49) months. These results show that using the conventional staging algorithm a substantial group of patients was understaged. FDG PET improves the selection of patients suitable for CMT.