Primary benign tumours of the spleen are rare, the majority originating from vascular endothelium.1 Most are haemangiomas, usually presenting as small, localised lesions, whereas splenic lymphangiomas are less common and often comprise multiple cystic lesions. Blood and lymphatic vessels share a common endothelial progenitor, of interest given two previous reports of splenic vascular lesions showing haemangiomatous and lymphangiomatous differentiation resulting in a haemangiolymphangioma in patients with Klippel-Trenaunay syndrome (KTS). We report the first case of haemangiolymphangioma simultaneously involving spleen and bone marrow.

A 49-year-old woman presented with a right upper abdominal mass and pain, but without B symptoms or pruritus. She had a 7-year history of a platelet storage pool defect with a mild thrombocytopenia, and had had a hysterectomy for menorrhagia. On examination she had an enlarged firm spleen palpable to the umbilicus but with no lymphadenopathy.

Abdominal ultrasound demonstrated an enlarged spleen which on CT showed a heterogeneous signal (figure 1). The liver was normal and there was no lymphadenopathy. Full blood count showed mild thrombocytopenia, microcytic anaemia and a normal white cell count and a blood film showed tear-drop poikilocytes suggestive of myelofibrosis. A bone marrow biopsy showed slightly hyperplastic, left shifted, reactive-type trilineage haematopoiesis, together with infiltration by a benign cavernous vascular proliferation (figure 2). Two-thirds of this lesion consisted of lymphatic spaces containing proteinaceous fluid (figure 2A), and a third of thin-walled capillary blood vessels (figure 2B) indicating a combined capillary haemangioma and lymphangioma; vascular endothelial cells were …