OBJECTIVEFurther investigation on the incidence and clinicopathologic features of bronchioloalveolar carcinomas (BAC) including: (1) BAC of strictly defined, (2) adenocarcinoma with bronchioloalveolar features, (3) other different histologic subtypes of lung adenocarcinomas.

METHODSSurgical specimens from 348 lung adenocarcinoma patients admitted in that hospital between 1998 - 2005 were included. And clinical data were collected at the same time. Patients of strictly defined BAC, BAC with focal invasion (BWFI), and adenomas with bronchioloalveolar features (AWBF) were followed-up. Data were analyzed using SPSS statistics software and Kaplan-Meier survival curves were constructed.

RESULTSThe resected lung adenocarcinomas consisted of different histologic subtypes. The most frequent one was adenocarcinoma of mixed subtypes (78.2%, 272/348), followed by the acinar type (8.1%, 28/348), the papillary type (4.0%, 14/348), the BAC (3.7%, 13/348), the mucinous (colloid) type (3.4%, 12/348) and the solid types (2.3%, 8/348). The fetal adenocarcinoma was the least component detected. There was no significant difference on the survival curves between groups BAC and BWFI. The survival rate of patients with AWBF was poorer than that of BAC and BWFI.

CONCLUSIONSSince patients with strictly defined (simple) BAC, BWFI, and AWBF have their own distinct clinicopathologic features and prognosis respectively, they should be strictly distinguished from other types of pulmonary adenocarcinomas.