Pulmonary granular cell tumor coexisting with interstitial lung disease - a rare case report.

A granular cell tumor (GCT) is a soft tissue neoplasm of rare occurrence in the lung. A 44-year-old male asphalt worker had interstitial lung disease. Incidentally, a 7 mm polypoid nodule was observed at the entrance of the right upper lobe bronchus. Tumor cells were characterized by a large granular eosinophilic cytoplasm and small, uniform nuclei. The neoplastic cells were diffuse positive for S-100, CD-68, NSE, vimentin, and SOX-10, and focal positive for calretinin and inhibin A. This case is unique in its distinction as the second literature case of pulmonary GCT coexisting with interstitial lung disease.