Liquid-based sputum cytology of bicomponent mucin-producing adenocarcinoma of the trachea with histologic comparison.

Primary tracheal adenocarcinomas are rare. Here, we report on the liquid-based sputum cytology of a bicomponent mucin-producing tracheal adenocarcinoma with histologic and immunohistochemical comparison. A 72-year-old man presented with dyspnea. Computed tomography revealed a lobulated mass in the mid-trachea. Sputum cytology showed clusters of atypical cuboidal cells that have pleomorphic and hyperchromatic nuclei and intracytoplasmic mucin. There were additional bland-looking components of regular clusters of cuboidal epithelial cells. These cells were initially evaluated as benign cells. Sleeve resection revealed a 3.7-cm-sized transmural mass, composed of tubulopapillary cuboidal epithelial cell structures. Half of the tumor comprised of bland-looking epithelial cells with small nuclei and eosinophilic cytoplasm; the remainder comprised of hyperchromatic cells with larger, distinct nucleoli. Direct interfaces between these components were observed, and both of these components equally displayed the characteristics of invasion and p53 expression. Two cell types in sputum cytology were retrospectively evaluated as adenocarcinomas of different grades. The patient has not shown recurrence for 8 months, postoperatively. Diagn. Cytopathol. 2016;44:1120-1124. © 2016 Wiley Periodicals, Inc.