[A case of adenoid cystic carcinoma manifesting Garcin's syndrome--effectiveness of cerebrospinal fluid ferritin as a tumor marker in malignant CNS involvement].

We reported a 69-year-old man exhibiting Garcin's syndrome caused by adenoid cystic carcinoma of the right submandibular gland. The patient first experienced abnormal sensations in his right cheek, and the cranial nerves on his right side gradually became affected. He was admitted for hoarseness and dysphagia. Physical examination revealed a right submandibular mass, and neurological examination revealed that the first cranial nerve and the fifth to twelfth cranial nerves on the right side were affected. Laboratory examination showed a rise of both serum and cerebrospinal fluid (CSF) ferritin, suggesting an intracranial invasion of the submandibular tumor. But other tumor markers, CSF protein and cell counts, CSF pathologic study and radiological studies for the central nervous system (CNS) were all negative. A submandibular tumor biopsy revealed adenoid cystic carcinoma. The radiation therapy, including the skull base, provided relief of the patient's symptoms, the tumor was reduced and serum and CSF ferritin level decreased. It is possible that CSF ferritin is a sensitive marker for CNS involvement of malignant tumor because of its permeability of the blood brain barrier and the absence of correlation between serum and CSF.