A 24 year old woman presented with a painless abdominal lump of six months’ duration. She had no history of colonic polyps. A mobile, non-tender, globular mass was felt in the umbilical region. A computed tomography scan showed a homogenous, non-enhancing mass, possibly arising in the small bowel mesentery.

The tumour was resected entirely with a loop of jejunum. The tumour measured 14 × 12 × 10 cm and was intimately related to the bowel wall. The cut surface was tan, whorled, and firm, without necrosis, cystic change, or haemorrhage. Microscopy showed loosely and haphazardly arranged spindle cells with bland, oval nuclei and minimal cytoplasm (figs 1 and …