['Prognostic factors for stage IB lung cancer remain controversial. The International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society proposed a new classification for pulmonary adenocarcinoma. We investigated the prognostic value of this new classification in resected stage IB pulmonary adenocarcinoma.', 'The study included 187 patients with stage IB pulmonary adenocarcinoma. All pathologic slides were reevaluated according to the new classification for pulmonary adenocarcinoma, with each histologic component recorded in 5% increments. Survival analyses were performed to determine the prognostic factors for stage IB pulmonary adenocarcinoma.', 'Univariable analysis showed tumor size was prognostic for overall survival (hazard ratio [HR], 2.083; p\xa0<\xa00.001) and progression-free survival (HR, 1.991; p < 0.001); gender (HR, 0.558; p\xa0= 0.033), presence of the solid component (HR, 1.976; p\xa0= 0.016), and presence of a micropapillary component (HR, 2.371; p\xa0= 0.018) were prognostic for progression-free survival. Multivariable analysis revealed that tumor size was an independent prognostic factor for overall survival (HR, 2.083; 95% confidence interval, 1.433 to\xa03.029; p < 0.001) and progression-free survival (HR, 2.036; 95% confidence interval, 1.546 to 2.681; p < 0.001) and that the\xa0presence of the solid component (HR, 2.045; 95% confidence interval, 1.172 to 3.568; p\xa0= 0.012) was an independent\xa0prognostic factor for progression-free survival.'] Do solid component and tumor size correlate with prognosis of stage IB lung adenocarcinoma?