Incidental granular cell tumor at the ileocecal junction mimicking a lymph node metastasis in a patient with history of neuroendocrine tumor of the right colon.

Abstract

Granular cell tumors are rare neoplasms originating from Schwann cells found in various organs. GCTs are seldom reported in the gastrointestinal tract. Pre-operative detection and diagnosis of colonic GCTs is challenging since the tumors are mainly asymptomatic, small, slow-growing, and submucosal. Most of these tumors are benign in histopathology and behavior. Recently, there has been greater insight into the varying presentations and behaviors of colonic GCTs with atypical histopathologic features. To contribute, we describe a GCT (2.3 cm) at the ileocecal junction found incidentally during follow-up for an excised ileal neuroendocrine tumor in a 65-year-old woman. Our GCT had an unusual focal atypia and infiltrative behavior into the pericolonic adipose tissue without metastasizing to the lymph nodes. These features are important since GCTs have a propensity for local recurrence if incompletely excised, which could have been easily missed. Even though GCTs with atypical features have low rates of recurrence and metastasis, they require close and careful attention in the absence of specific management guidelines due to potential aggressive behavior.