Prognostic factors in T1 NO MO adenocarcinomas and bronchioloalveolar carcinomas of the lung.

Abstract

There are few prognostic factors for patients with T1 N0 M0 pulmonary conventional and bronchioloalveolar adenocarcinomas (BACs), despite a 25% to 35% failure rate. To identify prognostic factors related to disease-free survival, we retrospectively studied the histologic features of 218 cases of T1 NO MO adenocarcinomas. The mean overall follow-up was 5.9 years, and the 5-year disease-free survival was 72%; 148 patients (67.9%) were disease-free, and in 57 (26.1%), nonpulmonary metastases developed. Features significantly associated with decreased 5-year disease-free survival were larger tumor size, increasing central fibrosis, most common and highest nuclear grade, lymphatic vascular space invasion, and more than 50% tumor necrosis. Patients with lymphatic vascular space invasion had a 35% 5-year metastases-free survival. A tumor size of 2 to 3 cm, lymphatic vascular space invasion, highest nuclear grade 3, and increased central fibrosis were associated with metastases. Lymphatic vascular space invasion had the strongest odds ratio of 5.4. These histologic features can stratify patients with T1 N0 M0 neoplasms who have an increased risk of metastases. Future studies are needed to address the usefulness of adjuvant therapy for patients with neoplasms that display these negative factors.