Predicting pleural invasion using HRCT and 18F-FDG PET/CT in lung adenocarcinoma with pleural contact

To evaluate the relevance of high-resolution computed tomography (HRCT) findings and fluorine-18-fluorodeoxyglucose ((18)F-FDG) uptake for risk stratification of visceral pleural invasion by lung adenocarcinoma.

The HRCT findings and (18)F-FDG uptake for lung adenocarcinomas with pleural contact on CT were retrospectively analyzed in 208 consecutive patients (94 females and 114 males; median age, 69.0 years) between January 2009 and December 2013, with institutional review board approval. The HRCT findings and maximum standardized uptake value (SUV max) were recorded for each patient. Multivariate logistic regression was used for statistical analysis, and subgroup analysis stratified for whole tumor size ≤ 3 cm was also performed.

Multivariate analysis showed that SUV max [odds ratio (OR) 1.09, 95 % confidence interval (CI) 1.02-1.16, P = 0.014] and obtuse angle (OR 4.14, 95 % CI 1.97-8.74, P < 0.001) were significant independent predictors for visceral pleural invasion. Receiver operating characteristic (ROC) analysis showed that, compared with the multivariate models [area under the curve (Az) 0.819-0.829], SUV max alone (Az 0.815) was useful in predicting visceral pleural invasion. In the subgroup analysis, multivariate analysis showed that SUV max (OR 1.29, 95 % CI 1.12-1.50, P = 0.001) and contact length with the pleura (OR 1.13, 95 % CI 1.05-1.22, P = 0.001) were significant independent predictors for visceral pleural invasion. ROC analysis showed that SUV max alone (Az 0.844) showed similar diagnostic performance to the multivariate models (Az 0.845-0.857).

SUV max alone and multivariate models including SUV max are useful for the prediction of visceral pleural invasion by lung adenocarcinoma.