[Cytological diagnosis and differentiation of tracheobronchial cylindromas]

From study of histocytological parallels in 12 cases of cylindromas the authors determined the criteria of cytologic diagnosis which allowed these tumors to be differentiated from other neoplasms of the lungs. Cylindromas are characterized by the presence in the cytogram of 2 types of cells (small cells and larger ones with light nuclei), homogeneous spherical structures with cells occurring centrally or on the periphery, ball-shaped clusters of cells, and an oxyphilic structureless mass forming the background of the preparation. The absence of oxyphilic masses in solid cylindroma, atypism and polyphormism of the epithelial cells makes it very difficult to differentiate it from moderately and poorly differentiated glandular carcinoma. However, careful study of the preparations and the discovery of an intermediate substance makes it possible to differentiate cylindroma from glandular carcinoma.