Usefulness of 18F FDG PET/CT in preoperative staging of NSCLC patients

Objectives To evaluate the usefulness of integrated positron emission tomography and computed tomography (PET/CT) in preoperative staging of patients with non-small cell lung carcinoma (NSCLC).

Methods Twenty nine histopathologically proven patients of NSCLC having CT based staging were subjected to 18F FDG PET/CT imaging. Whole body imaging (base of skull to mid thigh region) was performed in all patients.

Results Based on staging, disease was considered as nonresectable if staging ≥ IIIB. Of the 29 patients studied, CT showed resectable disease in 21 & nonresectable in 8 patients; PET/CT showed resectable disease in 15 & nonresectable in 14 patients. By PET/CT findings, 7 patients were changed from resectable to non-resectable group and one patient from non-resectable to resectable group. Hence, in 27.5% (8/29) of patients, change in management was achieved. PET/CT upstaged 12 patients (41.3%), downstaged 3 patients(10.3%) & confirmed staging in 14 patients (48.3%) compared to CT. Upstaging was done by the finding of nodal status in 6 and metastases in 6 patients. PET/CT downstaged 3 patients. (One suspected liver metastasis was found to be benign; mediastinal nodal involvement was ruled out in two patients). PET/CT was found to be more useful in the evaluation of nodal status and metastasis involvement which are the major determinants of resectability in patients with NSCLC.

Conclusions PET/CT showed excellent utility in the initial staging of patients with NSCLC. PET/CT changed the management, by deferring futile surgery, in approximately 24% of the patients. PET/CT should be considered mandatory in all patients considered to have resectable NSCLC