Solid predominant histologic subtype and early recurrence predict poor postrecurrence survival in patients with stage I lung adenocarcinoma

Introduction: This study investigated the correlation between histologic predominant pattern and postrecurrence survival (PRS), and identified the clinicopathologic factors influencing PRS in patients with completely resected stage I lung adenocarcinoma. Methods: A total of 136 stage I lung adenocarcinoma patients who experienced tumor recurrence after completely resection were included in this study. To analysis the association between histologic predominant pattern and PRS, invasive adenocarcinomas with mixed histologic components were divided into 2 groups: solid and nonsolid group (including lepidic, acinar, papillary, micropapillary) based on the histologic predominant pattern. PRS was analyzed to identify the prognostic predictors using the Kaplan-Meier approach and multivariable Cox models. Results: For all stage I invasive adenocarcinoma patients, the majority of postsurgical recurrences occurred within 2 years. Patients with solid predominant histological pattern were associated with unfavorable PRS (HR, 2.40; 95% CI 1.13-5.08, p=.022). There was a significant difference for poor PRS for patients who diagnosed tumor recurrence shorter than 12 months after surgery (HR, 2.34; 95% CI 1.12-4.90, p=.024). Extrathoracic metastasis was associated with poor media PRS in univariable analysis (p =.011), however, there was no significant PRS difference in multivariable analysis (HR, 1.56; 95% CI 0.65-3.73, p=.322) compared with intrathoracic metastasis. Conclusions: Solid predominant histologic subtype and recurrence free interval less than 12 months predict worse PRS in patients with stage I lung adenocarcinoma.