Granular Cell Tumor: Report of 13 Cases in a Veterans Administration Hospital

Granular cell tumors (GCTs) are of neuroectodermal origin and account for 0.5% of soft tissue tumors. They are most prevalent in African-Americans in the fourth to sixth decades, with a predilection for the head and neck regions. GCTs usually resemble more common lesions and hence are difficult to diagnose preoperatively. The tumor is readily identified on needle biopsy. Although usually benign with a malignancy rate of only 2-3%, the malignant form has a reported 3-yr mortality of 60%.

Clinical records of the Gulf Coast Veterans Healthcare System were surveyed for the period 1996-2016. Thirteen cases of GCT were found and reviewed for demographics, clinical course, method of diagnosis, management, and outcome.

All patients had a solitary GCT. Eleven lesions were benign and two were atypical. Sites involved were skin (8), colon (2), larynx (1), bronchus (1), and esophagus (1) (see Table I). The two atypical lesions occurred in the skin and larynx. Skin tumors were slow-growing, painful nodules, and, except for the two with preoperative needle biopsies, were misdiagnosed as epidermal inclusion cysts, lipoma, and papillary condyloma. Two colon lesions resembling a sessile polyp and submucosal lipoma, respectively, were found on colonoscopy performed for occult blood in the stool. The bleeding was attributed to adenomatous polyps also present. An atypical laryngeal GCT, found on laryngoscopy for hoarseness, was removed by submucosal resection. A bronchial GCT, excised during bronchoscopy for atelectasis, required re-excision 3 mo later. The esophageal GCT was an incidental finding on EGD for a dilated esophagus and gastric outlet obstruction. The patient declined surgical excision and elected MRI follow-up.

Granular cell tumors are infrequent and usually resemble more common lesions. Although almost always benign, the malignant form has a very poor prognosis. It is important to identify GCT preoperatively by fine-needle aspiration or core needle biopsy to improve outcome.