Reply to Matsushita et al.

Further to the letter by Matsushita et al., we basically agree with their opinion that ESD could be dangerous and requires advanced endoscopic skills when performed within the colonic lumen, a thin-walled structure. Fortunately, in our case it was possible to make the giant lipoma hang from the colonic wall by controlling the body position of the patient, and this made it easy to preserve the muscle layer.

Of course, our first impression of the submucosal tumor was that it was a colonic lipoma but one cannot rule out the possibility of malignancy (e. g. liposarcoma). It is our basic strategy to treat a histopathologically unknown mass as a ”tumor” that should undergo total en-bloc resection.

Although endoscopic snare unroofing would be an easy and swift procedure, giant masses are usually accompanied by feeding arteries, even in the case of lipoma. From the surgical point of view, it would always be safest to identify the arteries and subject them to electrocoagulation, even if this is more time consuming than other procedures. In fact, we did encounter an artery in this case, which was apparently feeding the tumor, and we coagulated it under endoscopic view. The decision depends on the judgement of risk of postresection hemorrhage.

Finally, our case does not suggest that all colonic lipomas should be resected by ESD but we do propose an indication for ESD in selected cases of submucosal tumors, and hence the title of our paper: ”Is endoscopic submucosal dissection really contraindicated for a large submucosal lipoma of the colon?”

Competing interests: None