Abstract
Three cases of differentiated papillary adenocarcinoma otiginating in the large bronchi of the 2nd to 6th orders and proliferating in a medial direction intraluminally along the bronchial surface are presented.
Light microscopically, these tumors were composed of cuboidal cells but free of fibrotic foci, scars and psammoma bodyies.
Electron microscopically endoplasmic reticulum, abundunt mitochondria and oval granules of the varying sizes with varying electron densities were noted, in 2 of the cases. But no mucous granules were observed.
Histogenetically, the 3 cases seemed to have originated in the bronchial surface epithelium.
