Accumulation of foamy lipid-laden histiocytic cells is most often seen in the skin and tendons, usually associated with congenital or acquired hyperlipidaemia, as seen in patients with diabetes mellitus, obstructive jaundice, and familial hypercholesterolaemia. The pathogenesis of xanthomatous lesions in other sites, including the urinary bladder,1 prostate,2 and gastrointestinal tract seems to be less consistent. Within the gastrointestinal tract the gastric mucosa is the most frequently cited location. Involvement of the oesophagus and bowel has rarely been described. Only three such cases largely confined to the small bowel have previously been documented. We here present an additional small bowel example accompanied by a short review of the existing literature in English on gastrointestinal xanthomatous lesions, including a discussion on its possible pathogenesis.

Histologically, the lesion is unique and a correct diagnosis does not pose significant difficulties. Identification of diverse phagocytosed cytoplasmic deposits in other histiocytic lesions may require ancillary studies. More importantly, malignant lesions composed of clear cells or signet ring cells, primary or metastatic,3 4 need consideration. With a high index of suspicion coupled with appropriate histochemical and immunohistochemical reactions, the correct diagnosis will easily be accomplished. The process is characterised by aggregates of foamy histiocytes, unaccompanied by fibrosis or giant cells as seen in xanthogranulomatous lesions.5 Well-defined clusters of such foamy histiocytes have been labelled xanthoma.6^–8 The diffusely infiltrating counterpart has been termed xanthomatosis.9 10 When forming a bulky mass lesion, the label xanthomatous pseudotumour has been applied11 12 and the subtle collection of xanthoma cells is often referred to as xanthelasma.13 In this letter we collectively refer to these lesions, which may be related, as xanthomatous lesions (XAN).

Case report

A woman in her 70s with a CT-verified ruptured infrarenal abdominal aortic aneurysm was admitted for surgery. Her past …