Clinical Snapshot
Granular Cell Tumor at an Unusual Site
;
A 54-year-old female patient with known chronic obstructive pulmonary disease (COPD) (GOLD II E, 70-pack-year history of smoking) and bronchiectasis underwent bronchoscopy to collect samples for microbiological analysis. During the procedure, an incidental finding was made of a whitish, plaque-like, slightly polypoid tumor measuring approximately 4 mm in the right lower lobe bronchus, which was removed with a cryoprobe (Figure a). Histomorphological analysis revealed a granular cell tumor—a soft tissue tumor rarely found in the bronchial system with neuroectodermal differentiation and characterized by the typical finely granular nature of the broad, intensely eosinophilic tumor cell cytoplasm and diagnostically confirmatory S100 immunoreactivity (Figure b). Granular cell tumors can mimic carcinoma due to frequent pseudoepitheliomatous hyperplasia of the surface epithelium. However, their biological behavior is benign in most cases (> 99%). Granular cell tumors are typically located in the head and neck region and the upper gastrointestinal tract, particularly the esophagus, but they may occur virtually anywhere and, in rare cases, in multilocular form. Benign granular cell tumors have an excellent prognosis after excision and do not require further treatment. Bronchoscopic follow-up is recommended and, in our case, showed local healing and tumor-free status after 3 weeks. Smoking has not been described as a risk factor for these tumors.
Prof. Dr. med. Benjamin Goeppert, Institut für Pathologie, RKH Klinikum Ludwigsburg, benjamin.goeppert@rkh-gesundheit.de
Dr. med. Tobias Merk, Klinik für Pneumologie, RKH Klinikum Ludwigsburg
Conflict of interest statement: The authors state that no conflict of interest exists.
Translated from the original German by Christine Rye.
Cite this as: Goeppert B, Merk T: Granular cell tumor at an unusual site. Dtsch Arztebl Int 2026; 123: 70. DOI: 10.3238/arztebl.m2025.0137
