Early Gastric Cancer with Diffuse Lanthanum Deposition.

A 50-year-old man with a history of long-term dialysis and who had been treated with lanthanum carbonate hydrate (a calcium-free phosphate adsorbent) underwent screening gastroscopy. Yellowish-white depositions, similar to those in xanthoma, were observed throughout the gastric antrum (Picture 1A) and the body (Picture 1B). A depressed area was observed among the depositions on narrow band imaging (Picture 1C, D), and the examination of a biopsy specimen confirmed Group 5 adenocarcinoma. The patient’s serum was negative for anti-Helicobacter pylori IgG, an H. pylori stool antigen test was negative and the patient had no history of H. pylori eradication. Following endoscopic submucosal dissection (Picture 2A), a histological examination showed a brownish deposition, which was suspected to be lanthanum carbonate hydrate, around papillary adenocarcinoma (Picture 2B). An immunohistochemical analysis confirmed the presence of CD68-positive macrophages, which were engulfing the brownish substance (Picture 2C).

Picture 1.

Picture 2.

The pathogenicity of gastric lanthanum deposition has been largely unexplored (1). To our knowledge, this is the first report of gastric mucosal lanthanum deposition that presented with neoplastic changes in the stomach. The further accumulation of cases will be necessary to clearly elucidate the relationship between lanthanum deposition and gastric cancer.

The authors state that they have no Conflict of Interest (COI).