Granular cell tumor experience at a comprehensive cancer center

Background: Granular cell tumors (GCTs) are rare lesions occurring almost anywhere in the body. Multiple case reports have been published. However, there are very few large-scale studies regarding GCT. The aim of this study was to define characteristics, treatment patterns and outcomes of patients with GCT. Methods: An institutional review board–approved retrospective chart review was performed. Descriptive statistics, chi-square analyses, and Kaplan–Meier survival estimates were produced. Results: Fifty patients were treated for GCT at our institution between 1992 and 2015. The median age was 47 y; 62% of patients were female and 64% were whites. Median tumor size was 0.8 cm. Four percent of patients had malignant tumors, 10.0% had atypical tumors, and 86.0% had benign tumors. The most frequent location of tumors was the gastrointestinal tract (n = 30; 60%), followed by skin/subcutaneous tissues (n = 19; 38%), then respiratory tract (n = 1; 2%). Most patients underwent surgical excision or endoscopic removal of their tumors without prior biopsy. Three patients (6%) had multifocal tumors; they were more likely to experience recurrence than patients with unifocal tumors (33.3% versus 10.6%, respectively; P = 0.05). Six patients (12.0%) experienced recurrence, with a median time to recurrence of 13.5 mo. Overall cancer-specific 5-y survival was 98.0%. Overall recurrence-free 5-y survival was 86.4%. Patients with atypical tumors had a lower recurrence-free 5-y survival rate than those with benign tumors (75.0% versus 89.7%, respectively; P = 0.04). Conclusions: Patients with GCT fair well, particularly when tumors are benign. Patients with multifocal tumors are more likely to experience recurrence and should be closely monitored.