Multicentric giant cell tumours in an adolescent with haemophilia.

''Multicentric giant cell tumour (GCTs) of the extremity is prone to be distributed over the age range of 20-40 years, but is rare in haemophilia and in the age before 20. We report a case of a 15-year-old haemophilia boy who presented initially with two radiolucent loci in the right femur and tibia revealed from the X-ray films and then another lesion in the posterior femoral shaft shown from MRI by one year. Differential diagnosis of GCTs should be appraised in various aspects. Radiological diagnostic pitfall was avoided by the pathology disclosed GCTs without malignancy. The early diagnosis of GCTs in haemophilia may be delayed unless appearance of symptoms of pathologic fracture. Coincident multicentric GCTs do occur in haemophilic patients and their incidence might be underestimated, as it might not be judged because immediate symptoms of pain would resolve with appropriate factor replacement."