Malignant granular cell tumor at the retrotracheal space

We report a case of an extremely rare neoplasm, malignant granular cell tum or (MGCT). The patient was a 21-year-old woman, who was 5 months pregnant. The tumor occurred in the retrotracheal space, extending from the level of the larynx to the thoracic inlet. In addition there were multiple, variable -sized tumor nodules within both lung fields on chest CT scan. Histological ly, tissue biopsied from the periphery of the tumor consisted of solid shee ts of large ovoid cells with ample, eosinophilic cytoplasm, eccentric nucle i, and prominent nucleoli. Each cell showed slight atypism of the nuclei. T here was a focal necrosis at the periphery of the lesion. These cells stain ed strongly for S-100 protein, neuron-specific enolase (NSE) and CD68. On e lectron microscopy, the tumor cells contained autophagic vacuoles. The pati ent refused further treatment and died 7 months later. The exact cause of d eath was not known. Until now, the diagnosis of MGCTs has been made only wh en metastasis and an aggressive clinical course are identified, although so me observers advocate that some histologic features such as nuclear pleomor phism, necrosis, and the presence of any mitotic activity are indicative of malignancy. These histologic findings are not easily detectable in every c ase of MGCT, as in our case. So the diagnosis of a MGCT should be considere d in cases with aggressive clinical findings and some histologic features, such as necrosis, nuclear atypism, and mitotic activities, which could sugg est the malignant behavior of this neoplasm.