Abdominal-wall myositis secondary to intra-arterial chemotherapy for femoral osteosarcoma.

[focal myositis]

With the increasing application of intra-arterial chemotherapy (IAC ), new side-effects are encountered . We describe two children with proximal femoral osteosarcoma who developed focal myositis of the abdominal wall musculature after IAC . In both cases , myositis presented as abdominal pain and mimicked acute abdomen . US demonstrated asymmetrical thickening of abdominal -wall musculature in the right lower abdomen . This diagnosis should be considered when evaluating the patient with unexplained abdominal pain and a history of IAC .