Prognostic significance of using solid versus whole tumor size on high-resolution computed tomography for predicting pathologic malignant grade of tumors in clinical stage IA lung adenocarcinoma: A multicenter study

Objectives The present multicenter study compared the usefulness of the solid tumor size with that of the whole tumor size on preoperative high-resolution computed tomography for predicting pathologic high-grade malignancy (positive lymphatic, vascular, or pleural invasion) and the prognosis of clinical stage IA lung adenocarcinoma. Methods We performed high-resolution computed tomography and F-18 fluorodeoxyglucose-positron emission tomography/computed tomography before curative surgical resection in 502 patients with clinical stage IA lung adenocarcinoma. The revised maximum standardized uptake values on F-18 fluorodeoxyglucose-positron emission tomography/computed tomography were used to correct interinstitutional discrepancies. The whole and solid tumor sizes on high-resolution computed tomography were then analyzed in relation to surgical results. Results The mean whole and solid tumor size was 1.97 ± 0.59 cm and 1.20 ± 0.88 cm, respectively. The receiver operating characteristics area under the curve for the whole and solid tumor sizes used to identify high-grade malignancy were 0.590 and 0.829, respectively. Multiple logistic regression analyses demonstrated solid tumor size ( P