OBJECTIVETo investigate the clinical value of 18F-fluorodeoxyglucose positron emission tomography (FDG PET)/CT for the diagnosis and management of lung nodules.

METHODSTwenty patients were evaluated: 15 with suspected cancer and 5 confirmed cancer. PET/CT scans were performed by discovery LS-PET/CT system.

RESULTS(1) The diagnostic accuracy of PET/CT was 100% in these 20 patients. Of 15 patients with suspected cancer, 7 were diagnosed as having benign disease and 8 malignant. All the 5 patients with confirmed cancer were all FDG positive. Of 11 single lesions on CT, 3 were positive by PET/CT images, 6 of 8 with positive CT images were diagnosed as having metastasis to the tissue outside the lung and the other 2 were metastatic. (2) After PET/CT scanning, the therapy scheme of 16 out of 20 patients were changed, and continual observation was practiced in 2, 3 were treated by anti-inflammation regimen, 2 by operation, 4 by local radiotherapy, 3 by chemotherapy only, 4 by radiotherapy plus chemotherapy or operation. (3) The radiotherapists made use of PET/CT fusion imaging for positioning in 8 patients who were indicated for radiotherapy. One of them who had received MM50 one course of intensity medulated conformal radiotherapy was re-examined by PET/CT after one and half months, the former parenchymal nodule disappeared and the glucose metabolism returned to normal. Two of them were finally operated after the surgeons have decided an operative approach on estimation of extent of lesion by the PET/CT fusion images. Pathological results showed no cancer cell involvement in the specimen margin or the local lymph nodes.

CONCLUSION(1) PET/CT is better in discriminating malignant from benign lung nodules than CT only. (2) PET/CT scanning facilitates an accurate assessment of response in clinical staging and neoadjuvant therapy scheme of lung cancer. (3) PET/CT fusion imaging provides an accurate biological target for radiotherapy and confirms the operation plan and extent of surgery.