The maximum standardized 18F-fluorodeoxyglucose uptake on positron emission tomography predicts lymph node metastasis and invasiveness in clinical stage IA non-small cell lung cancer.

In patients with clinical stage IA non-small cell lung cancer (NSCLC), we investigated whether the maximum standardized uptake value (SUVmax) of 18F-fluorodeoxyglucose (FDG) by the tumor correlated with lymph node metastasis, intratumoral lymphatic and vascular invasion of tumor cells, and pleural invasion. From April 2005 to November 2008, 58 patients underwent a lobectomy with systematic hilar and mediastinal lymph node dissection for clinical stage IA NSCLC. All patients had integrated FDG-positron emission tomography (PET)/computed tomography (CT) performed in our center as part of the preoperative workup within one month of resection. The relationships between the SUVmax and pathologic results of lymph node metastasis, intratumoral lymphatic and vascular invasion of tumor cells, and pleural invasion were examined. Compared with tumors with an SUVmax < or = 2.0, tumors with an SUVmax>2.0 had more frequent lymph node metastasis, intratumoral lymphatic and vascular invasion of tumor cells and pleural invasion (all P<0.05). Our results suggest that in patients with clinical stage IA NSCLC, SUVmax is an important predictor of tumor invasiveness.