The value on SUV-derived parameters assessed on 18F-FDG PET/CT for predicting mediastinal lymph node metastasis in non-small cell lung cancer

Purpose To explore valuable predictors for mediastinal lymph node metastasis in non-small cell lung cancer (NSCLC) patients, we analyzed the potential roles of standardized uptake value (SUV)-derived parameters from preoperative .sup.18F-FDG PET/CT combined with clinical characteristics. Methods Data from 224 NSCLC patients who underwent preoperative .sup.18F-FDG PET/CT scans in our hospital were collected. Then, a series of clinical parameters including SUV-derived features [SUVmax of mediastinal lymph node and primary-tumor SUVmax, SUVpeak, SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG)] were evaluated. The best possible cutoff points for all measuring parameters were calculated using receiver operating characteristic curve (ROC) analysis. Predictive analyses were performed using a Logistic regression model to determine the predictive factors for mediastinal lymph node metastasis in NSCLC and lung adenocarcinoma patients. After multivariate model construction, data of another 100 NSCLC patients were recorded. Then, 224 patients and 100 patients were enrolled to validate the predictive model by the area under the receiver operating characteristic curve (AUC). Results The mediastinal lymph node metastasis rates in 224 patients for model construction and 100 patients for model validation were 24.1% (54/224) and 25% (25/100), respectively. It was found that SUVmax of mediastinal lymph node [greater than or equal to] 2.49, primary-tumor SUVmax [greater than or equal to] 4.11, primary-tumor SUVpeak [greater than or equal to] 2.92, primary-tumor SUVmean [greater than or equal to] 2.39, primary-tumor MTV [greater than or equal to] 30.88 cm.sup.3, and primary-tumor TLG [greater than or equal to] 83.53 were more prone to mediastinal lymph node metastasis through univariate logistic regression analyses. The multivariate logistic regression analyses showed that the SUVmax of mediastinal lymph nodes ([greater than or equal to] 2.49: OR 7.215, 95% CI 3.326-15.649), primary-tumor SUVpeak ([greater than or equal to] 2.92: OR 5.717, 95% CI 2.094-15.605), CEA ([greater than or equal to] 3.94 ng/ml: OR 2.467, 95% CI 1.182-5.149), and SCC (< 1.15 ng/ml: OR 4.795, 95% CI 2.019-11.388) were independent predictive factors for lymph node metastasis in the mediastinum. It was found that SUVmax of the mediastinal lymph node ([greater than or equal to] 2.49: OR 8.067, 95% CI 3.193-20.383), primary-tumor SUVpeak ([greater than or equal to] 2.92: OR 9.219, 9