[A case of Collet-Sicard syndrome caused by skull base metastasis of prostate carcinoma].

A case of Collet-Sicard Syndrome caused by skull base metastasis of prostate carcinoma is reported. A fifty-five years old man presenting multiple lymph node and bone metastases of prostate carcinoma was treated with LH-RH agonist and Flutamide, which induced transient decrease in serum PSA levels and size of lymph node metastases. After 8 months of the treatment, the patient started complaining headache, dysphagia and dysarthria. Brain CT and MRI demonstrated a soft tissue mass replacing left pyramidal bone and occipital bone around left jugular foramen. The tumor was diagnosed as skull base metastasis of the prostate carcinoma and was treated with 50Gy of radiation. The symptom improved after the radiation but died of the disease in 4 months. The autopsy revealed the skull base metastasis of the prostate carcinoma and the tumor was proved to be poorly differentiated adenocarcinoma, which was positively stained by anti-PSA antibody. The case showed cranial nerve palsy of IX to XII, which is usually called Collet-Sicard syndrome. This is the third case report of Collet-Sicard syndrome caused by the skull base metastasis of prostate carcinoma, and it is the first case in Japan.