This is the typical appearance of a granular cell tumour (Abrikossoff’s tumour) first described in 1926 by Abrikossoff, a Russian pathologist.
These lesions can probably develop anywhere. Outside of the GI tract, the lesions are most commonly found at the tongue, head and neck. Within the GI tract, the oesophagus is the most common location. Lesions are rarely multiple (about 10% of cases). Granular cell tumours are said to be more common in women and black people.
The endoscopic features are typical as is histology showing cells containing an eosinophilic (pink/red) cytoplasm resembling granules which stain positive with the Periodic Acid Schiff stain. Immunohistochemical staining will be positive for S-100 protein and neuron-specific enolase (NSE). Stains for desmin, vimentin, and cytokeratin will be negative. Surface biopsies may fail to confirm the diagnosis as these nodules are submucosal. The differential diagnosis is that of a small lipoma or a leiomyoma (which are much more common in the oesophagus than in the stomach).
When detected these lesions are usually referred for endoscopic resection. Unfortunately, as the lesions arise from the deep submucosa, the local recurrence is high (30-40%). For this reason I now treat the raw EMR surface, immediately post-resection with APC set at low power (35W). A tiny proportion of these lesions (said to be less than 2%) are said to be malignant overall. However, the published literature is confusing as GI and non-GI lesions are frequently combined. Perhaps the only compelling reason for removing these from the oesophagus, is that it is cheaper than surveillance!
In the attached video, a small granular cell tumour is removed using the Olympus EMR cap. In a sedated and compliant European patient, you will probably have a “therapeutic window” of 20 minutes. Longer procedures are better carried out under general anaesthesia. All my oesophageal EMR’s are now carried out using the “Duette banding kit”. With this equipment, the resections can be carried out without the need for a submucosal injection in less than 3 minutes. Is used to have some trouble with bleeding and now set my ERBE diathermy unit on “level 4” (setting the device at a maximum proportion of coagulation in the blend mix when I press the yellow pedal) and “endocut” 120W. The Endocut setting senses the amount of power required and will only give you what is needed to cut the polyp up to a maximum ceiling power which you have selected (if more power is needed the device alarms). However, I know of some who carry out oesophageal EMR’s using “pure coagulation” (blue pedal).