Fig. 1

CT-scan and histological analyses. a: Axial section of abdominal CT-scan showing a pseudotumoral thickening of the right colonic wall (arrow) with diffuse peritoneal effusion (arrowhead). b: Right colectomy showing a tumoral proliferation developed from subserosal part of the bowel without infiltration of muscularis. c: Axial section of a cervical CT-scan showing a left sub-mandibular lymphadenopathy of 30 mm in diameter (arrow). d: The tumour comprised numerous histiocytes with crystals in eosinophilic cytoplasm (arrows). e: Histiocytes are positive for CD163. f: Crystals are positive for the kappa light chain