Localised massive tumourous xanthomatosis of the small intestine

There are various disorders of the intestine described with accumulations of vacuolated macrophages including single or multiple xanthelasmata, Wolman's disease, cholesteryl ester storage disease (CESD), xanthomatogranulomatotic disease and xantheloma disseminatum. In this paper, we report on an exceptional case of a 68-year-old male patient with a localised, massive accumulation of vacuolated, most likely lipid-loaded macrophages with an infiltrative pattern in the muscularis mucosa and propria of the small intestine leading to a tumourous mass requiring surgical removal due to impaired gut function. No enlargement of the liver or the spleen and no evidence of general abnormal lipid storage were detected elsewhere. No evidence of Wolman's or CESD was present. Also, on the ultra-structural level, the macrophages contained no cholesterol clefts typical for either Wolman's and CESD. Instead, largely empty, partly large vacuoles were seen, which most likely contained fatty acids removed during processing. The pathogenetic mechanism of the massive local accumulation of histiocytic cells in this part of the intestine in our case remains un-clear. In summary, this case demonstrates that on rare occasions histiocytic proliferations can mimic tumourous masses with severe functional impairment of the intestine and thus should be in the differential diagnosis of gastrointestinal motility disorders.