Multiple granular cell tumors of the gastrointestinal tract with subsequent development of esophageal squamous carcinoma.

A 52-year-old woman initially presented to our medical center with synchronous, submucosal tumors of the esophagus, stomach, and transverse colon. The gastric and colonic tumors were resected, and both displayed infiltrating sheets of polygonal cells with coarsely granular cytoplasm and small vesicular nuclei. The neoplastic cells of both tumors were immunoreactive for S-100 protein. Ultrastructural studies revealed the lysosomal nature of the cytoplasmic granules. Although the esophageal mass was not resected, it was felt that this represented another focus of granular cell tumor of the gastrointestinal tract. Two years later, she presented with disseminated squamous carcinoma of the esophagus. At autopsy, a submucosal granular cell tumor was found adjacent to the squamous carcinoma of the esophagus. To our knowledge, this is the first reported case of synchronous granular cell tumors that involved multiple segments of the gastrointestinal tract, one of which was later associated with a squamous carcinoma of the esophagus.