Impact of staging with 18F-FDG-PET on outcome of patients with stage III non-small cell lung cancer:: PET identifies potential survivors

Purpose: The aim of this study was to analyse the impact of FDG-PET staging on treatment results of neo-adjuvant radiochemotherapy in patients with advanced non-small cell lung cancer (NSCLC). We compared prospectively the outcome of two patient groups with stage III NSCLC undergoing the same neo-adjuvant radio-chemotherapy (NARCT). In one group, FDG-PET was part of the pretherapeutic staging, whereas in the other group, no PET scans were performed. Methods: One hundred and eighty-eight patients with advanced stage III NSCLC were selected for a phase II trial of NARCT. The first 115 patients underwent conventional workup (CWU) and FDG-PET before inclusion (group I); the remaining 73 patients underwent CWU only (group II). All patients were followed up according to a standardised protocol for at least 11 months (up to 64 months). Overall survival and disease-free survival were used as parameters of therapeutic success and analysed statistically. Results: After staging, 157/188 patients were included in the clinical trial. Thirty-one were excluded owing to the results of FDG-PET, in most cases because of the detection of previously unknown distant metastases. Overall survival and metastasis-free survival were significantly longer in patients of group I stratified by FDG-PET than in group II (p=0.006 and 0.02 respectively). Another significant factor for survival was complete tumour resection (p=0.02). Gender, histological tumour type, tumour grade and UICC stage had no significant influence. Conclusion: Pretherapeutic staging by FDG-PET significantly influences the results of NARCT and subsequent surgery by identifying patients not eligible for curative treatment.