Malignant carotid paraganglioma: a case report.

Tumors of the carotid body are uncommon neoplasms that originate in the neuroectoderm. These tumors are slow growing but well vascularized and very destructive. Between 5% and 13% of carotid body tumors are malignant, behaving aggressively at the local level, invading the adjacent lymph nodes, and resulting in remote metastases. We present the case of a 60-year-old man who was examined for pain and paresthesias in his arm. Magnetic resonance imaging showed a large tumor in the left carotid space. Histologic study of a biopsy specimen from the tumor revealed that it was a paraganglioma. Further studies to determine the extent of disease detected metastases in bone and lung, confirming the tumor's malignancy.