Current Thoracic Surgery

Background: Until the reclassification by the International Association for the Study of Lung Cancer, the term bronchoalveolar carcinoma (BAC) has been used for many years. Accordingly, the terms BAC and mixed adenocarcinoma were replaced by the terms such as adenocarcinoma in situ, minimally invasive adenocarcinoma, lepidic dominant type adenocarcinoma, mucinous minimally invasive adenocarcinoma, and mucinous invasive adenocarcinoma. The aim of this study was to retrospectively evaluate the cases diagnosed as BAC and mixed type adenocarcinoma operated in our clinic and to compare the clinical and survival characteristics of these cases according to the new classification.

Materials and Methods: 37 patients who were operated in our clinic between January 2005 and December 2014 and diagnosed as BAC and mixed adenocarcinoma containing BAC components were included in the study. Pathologic slides were re-reviewed by the pathologists of our hospital and reclassified according to the predominant histologic subtype. In addition to the predominant cell type, the ratio of other cell types were also specified in 5% ratio slices.

Results: The histopathological diagnoses of 37 formerly BAC patients, 14 of whom were mixed type, were changed as 33 lepidic, two mucinous, one adenocarcinoma in situ and one micro-invasive adenocarcinoma. The 5-year survival rate for lepidic predominant histological subtype was 70.3, while it was 50% (p = 0.533) for the two mucinous cases.

Conclusions: The predominant cell type distribution used in the new classification of IASLC is more effective in determining survival and is more suitable for use in treatment and follow-up programs.