Clinicopathologic analysis of 10 cases of pulmonary colloid adenocarcinoma and prognostic implication of invasive micropapillary component.

Colloid adenocarcinoma is a rare variant of lung adenocarcinoma with distinct clinicopathologic characteristics. The frequently seen ciliated tumor cells may suggest that this tumor might originate from a metaplastic process. Majority had indolent clinical course but presence of stromal invasion or micropapillary pattern may reflect aggressive behavior of colloid adenocarcinoma and may indicate poor prognosis.