Isolated hypoglossal nerve palsy due to skull base metastasis from breast cancer.

We describe a 44-year-old woman who presented with an isolated unilateral hypoglossal nerve paralysis caused by a skull base metastasis from breast cancer. The patient had a modified radical mastectomy followed by local radiotherapy and adjuvant chemotherapy. Fourteen months later she presented with difficulty in speaking. Physical examination revealed an isolated left hypoglossal nerve paralysis. The MRI scan showed a mass lesion involving the left occipital condyle extending into hypoglossal canal.