Cement-augmented dorsal instrumentation of the spine as a safe adjunct to the multimodal management of metastatic pheochromocytoma: a case report

摘要

Malignant pheochromocytoma is a neuroendocrine tumor that originates from chromaffin tissue. Although osseous metastases are common, metastatic dissemination to the spine rarely occurs. Five years after primary diagnosis of extra-adrenal, abdominal pheochromocytoma and laparoscopic extirpation, a 53-year old patient presented with recurrence of pheochromocytoma involving the spine, the pelvis, both proximal femora and the right humerus. Magnetic resonance imaging and computed tomography revealed osteolytic lesions of numerous vertebrae (T1, T5, T10, and T12). In the case of T10, total destruction of the vertebral body with involvement of the rear edge resulted in the risk of vertebral collapse and subsequent spinal stenosis. Thus, dorsal instrumentation (T8-T12) and cement augmentation of T12 was performed after perioperative alpha- and beta-adrenergic blockade with phenoxybenzamine and bisoprolol. After thorough preoperative evaluation to assess the risk for surgery and anesthesia, and appropriate perioperative management including pharmacological antihypertensive treatment, dorsal instrumentation of T8-T12 and cement augmentation of T12 prior to placing the corresponding pedicle screws did not result in hypertensive crisis or hemodynamic instability due to the release of catecholamines from metastatic lesions. To the authors' knowledge, this is the first report describing cement-augmentation in combination with dorsal instrumentation to prevent osteolytic vertebral collapse in a patient with metastatic pheochromocytoma. With appropriate preoperative measures, cement-augmented dorsal instrumentation represents a safe approach to stabilize vertebral bodies with metastatic malignant pheochromocytoma. Nevertheless, direct manipulation of metastatic lesions should be avoided as far as possible in order to minimize the risk of hemodynamic complications.