Introduction Granular cell tumours (GCTs) are rare and originate from Schwann cells of the nervous system. They are most commonly found in the tongue and breast. GCTs can form anywhere in the gastrointestinal tract and biliary tree but most commonly in the oesophagus. They occur primarily in adults, and more commonly in females and blacks. GCTs are asymptomatic and tend to be incidental findings at endoscopy. GCTs represent 1% of benign oesophageal tumours and have a small risk of malignant transformation when they are greater than 4 cm or exhibit signs of recent growth. Most are in the middle or distal oesophagus and are small appearing as nodules or polyps that are yellow with an intact overlying mucosa. Typically they are single but may be multiple. Histologically they appear as sheets of cells with abdundant eosinophilic granular cytoplasm and small pyknotic nuclei and usually confined to the lamina propria but may invade submucosa and muscularis propria. They are periodic acid shiff (PAS) and S100 positive on immunostaining. Importantly the squamous epithelium overlying the lesion can show pseudo epitheliomatous hyperplasia that may mimic dysplasia or malignancy.
Methods A retrospective search of the UCLH endoscopy and pathology databases from 2002–2015 identified all cases of oesophageal GCTs on histological analysis from biopsies. Patient’s medical records were reviewed for demographic data, symptoms, endoscopic findings and management plans.
Results Eleven cases of GCTs in the oesophagus (4 male and 7 female) were identified. Diagnosis was proven on histological analysis of biopsies and positivity for the S-100 protein. Patients were 29–65 years old (mean 46.2 years). Tumour diameter was 0.4–2.0 cm. All GCTs were found in the distal oesophagus. Nine of the lesions were confined to the mucosa/submucosa and two extended into the muscularis propria. The most common presenting symptoms for the index endoscopy were dyspepsia and dysphagia. Eight patients were treated by endoscopic mucosal resection (EMR). One patient had multifocal oesophageal GCTs. All patients had no residual GCT at follow up endoscopy and were discharged. Two patients with GCTs were monitored by 2 yearly surveillance endoscopy and endoscopic ulstrasound (EUS) to ensure no change in lesion size occurred. One patient had an oesophagogastrectomy for treatment of an adenocarcinoma and the GCT was an incidental finding.
Conclusion Histology demonstrating a deep infiltrative appearing pattern may prompt concern for malignancy. Surveillance endoscopy is advised for asymptomatic GCTs. GCTs that are not excised should be monitored by endoscopy and EUS for any size increase 1–2 yearly. EMR can be performed for small tumours limited to the mucosa safely and successfully.
Disclosure of Interest None Declared