Staging and Monitoring of Small Cell Lung Cancer Using [18F]Fluoro-2-deoxy-D-glucose-Positron Emission Tomography (FDG-PET)

Background:[18F]Fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) scan is widely used for the staging evaluation of nonsmall cell lung cancer, however, its use in small cell lung cancer (SCLC) remains investigational. Patient and Methods:We designed a prospective study to evaluate the role of PET in SCLC. Patients with SCLC underwent PET scanning as well as conventional imaging before and after treatment. Results:A total of 39 PET scan examinations were performed in 21 patients with SCLC; 18 studies were performed before first-line chemotherapy and 21 studies were done during or after treatment. PET findings were compared with findings on CT scans of the chest or abdomen and bone scan. Discordant findings were detected in 14 out of 383 comparisons (4%) for 10 anatomic sites. In the thorax and the abdomen, PET agreed with CT scan in 92% to 100% of examinations assessing potential disease sites, including the contralateral chest, liver, and adrenals. PET agreed with bone scan in detecting bony lesions in 27 out of 32 imaging studies (84%): in 4 out of 5 discordant cases, PET findings were true and in 1 case indeterminate. Staging at baseline (limited, n = 6; extensive, n = 12) was identical when PET and sum of other staging procedures were compared. Response assessment was concordant between PET and CT scans in 8 of 9 patients who had evaluation before and after first-line chemotherapy. Conclusions:PET is potentially useful for the initial staging and monitoring of patients with SCLC and it may be superior to bone scan in detecting bone metastasis. The cost effectiveness of PET scan in SCLC remains to be determined.