Bone metastases in pheochromocytoma: comparative studies of efficacy of imaging

Bone is the most common site of metastasis from pheochromocytoma. Now that the effects of hypercatecholaminemia can be adequately controlled with adrenergic blockade, pathologic fractures are becoming an increasingly significant cause of morbidity in patients with metastatic pheochromocytoma. Bone metastases from pheochromocytoma have not been extensively reevaluated since the advent of computed tomography (CT), high-resolution bone scintigraphy, and iodine 131 MIBG scintigraphy. Plain radiographs, CT scans, bone scans, and I-131 MIBG scans of 38 patients with pheochromocytoma bone metastasis were reviewed. The axial skeleton was the most common site of metastasis. Metastases typically appeared expansile and mixed lytic-sclerotic on radiographs. Bone scintigraphy was the most sensitive modality for detecting bone metastasis, with 74% of all alleged lesions being identified. In screening for bone metastasis from pheochromocytoma, bone scanning in conjunction with I-131 MIBG scanning is recommended, followed by scan- and symptom-directed radiography and - where a question still exists - CT.