A Rare Case of Endobronchial Granular Cell Tumors

Abstract

INTRODUCTION: Granular cell tumors are rare neoplasms primarily of neuroendocrine origin. They account for only 0.5% of soft tissue tumors. They most commonly occur in the head and neck region, with less than 10% of cases involving the respiratory tract. Due to their low prevalence, granular cell tumors are easily mistaken for more common tumors. This case highlights the presentation, diagnosis, and management of a patient with these rare tumors using a multidisciplinary approach.CASE PRESENTATION: A 41-year-old African American female smoker presented with atypical chest pain and dyspnea. Associated symptoms included fevers, chills, fatigue, cough productive of green sputum, and a 20 pound unintentional weight loss. She was hemodynamically stable with excellent oxygen saturation on room air. Physical exam was remarkable for slightly diminished breath sounds over the lower right lung field. CT chest demonstrated right hilar lymphadenopathy and a bulky, heterogenous 5.9 x 6.1 x 5.6 cm mass in the posterior medial right lower lobe. Bronchoscopy revealed several yellow, lobulated endobronchial lesions located in the right upper and lower lobes. Biopsies were obtained from both locations, resulting in PASþ, S100þ, and SOX10þ stains. Fine needle aspiration (FNA) of hilar and mediastinal adenopathy was performed via endobronchial ultrasound (EBUS) and was negative for malignancy. The combined morphologic and immunohistochemical findings were determined to be consistent with a granular cell tumor.The case was presented at the hospital center's multidisciplinary thoracic conference with a recommendation for formal surgical evaluation. Cardiothoracic surgery performed a right video-assisted thoracoscopic surgery (VATS) exploration and second biopsy of the right upper lobe mass, with pathology again consistent with granular cell tumor. Definitive treatment for this patient concluded with a right pneumonectomy.DISCUSSION: Granular cell tumors are rare, slow growing tumors presenting most often in the head and neck region. Persons in their 4th-6th decade of life are most commonly affected, with an increased incidence in African American females. When pulmonary involvement occurs, granular cell tumors may present as an endobronchial lesion or small solitary lung mass less. Diagnosis requires tissue acquisition and immunohistochemical staining. Granular cell tumors are typically benign, with a malignancy rate of less than 3%. There is little evidence to support the use of chemoradiation in treatment of these tumors. Surgical resection offers the best therapeutic option for curative treatment.CONCLUSIONS: Granular cell tumors are rarely occurring pulmonary neoplasms with a lack of standardized management recommendations. This case illustrates a multidisciplinary approach to identification, evaluation, and management of these rare neoplasms.