Isolated Oculomotor Nerve Palsy Due to Metastasis of Prostatic Cancer to the Cavernous Sinus.

A 69-year-old man with prostatic cancer under palliative care developed isolated right-sided oculomotor nerve palsy with pupillary impairment and persistent ocular pain. Cranial magnetic resonance imaging demonstrated metastasis of prostatic cancer to the right-sided cavernous sinus and orbital apex. In the English language literature, there are only six reported cases of isolated oculomotor nerve palsy secondary to prostatic cancer. In all cases, although there was metastatic lesion in the vicinity of the cavernous sinus, ocular pain did not develop. In the current patient, because metastatic tumour might involve the right-sided oculomotor nerve as well as lacrimal nerve, ocular pain developed.