Cerebral sparganosis is a rare disease; to date only eight cases have been described. Two new cases of cerebral sparganosis occurring in Chinese patients living in a metropolitan area are reported. Their clinical presentation and investigative results are presented and the operative and histological findings detailed. A brief review of the condition is given and the possible source of infection discussed.

A 42-year-old woman was noted to have a left neck lump in a health check-up. One year earlier, her mother was diagnosed to have poorly differentiated thyroid cancer. Ultrasound revealed a polygonal hypoechoic lesion without calcifications (Picture 1; asterisk, left thyroid). Fine-needle aspiration cytology was inconclusive. Based on suspicious ultrasonographic characteristics, she was brought to the operating room for diagnostic lobectomy. At surgery, a plane was identified between the well-encapsulated tumor and the thyroid gland. Enucleation was performed. Frozen section revealed characteristic nuclear palisading with Verocay bodies (Picture 2).The thyroid gland is close to laryngeal nerves and is innervated by sympathetic nerve branches (1). Neurilemmomas arise from Schwann cells. It is usually difficult to make a diagnosis by fine-needle aspiration because follicular cells are absent and the aspirated cells are hard to identify (2). Given that hereditary nonmedullary thyroid cancer is more aggressive, histopathologic diagnosis is recommended.