The tumors are typically peripherally located. In this image it is light tan and is composed of multiple diffuse nodules coalescing producing a "bronchopneumonia"-like consolidation grossly (these tumors may be confused with bronchopneumonia grossly).
Microscopy
Malignant glandular epithelial cells growing along alveolar walls in a lepidic pattern.
Nuclei of cells are hyperchromatic.
Types
mucinous type bronchioloalveolar carcinoma
non-mucinous type bronchioloalveolar carcinoma
References
Benjamin DR, Cahill JL. Bronchioloalveolar carcinoma of the lung and congenital cystic adenomatoid malformation. Am J Clin Pathol 1991; 95:889-92.