Cytology of endobronchial granular cell tumor

Cytologic features of four cases of endobronchial granular cell tumor are presented. The diagnostic cells were found in bronchoscopically obtained material. They were arranged in smaller clusters and had finely granular cytoplasm with uniform oval or round nuclei. Frequently the cells are overlooked on regular cytologic examination owing to their benign nature. Nevertheless, there are enough cytomorphologic features that help to distinguish these cells from macrophages and bronchial epithelial cells. It is essential that the possibility of granular cell tumor is considered on cytologic examination. Final diagnosis, however, requires histologic verification.