Cerebellopontine angle and internal auditory canal metastasis from ductal carcinoma of the breast.

This is the first formal case report of internal auditory canal and cerebellopontine angle metastasis from infiltrative ductal carcinoma of the breast. Only three previous cases have been reported of isolated metastasis in the cerebellopontine angle and internal auditory canal from breast cancer. Currently, no therapeutic guidelines for isolated metastasis from breast cancer in this location exist. We report a case and review the current literature in order to help characterize the clinicopathologic features and management. A 72-year-old female with a 5-year history of left infiltrative ductal carcinoma of the breast reported progressive left-sided facial palsy and ipsilateral hearing loss accompanied by the development of tinnitus and unsteadiness during the previous 3 months. MRI identified a lesion in the cerebellopontine angle and internal auditory canal. The lesion was completely excised via a retrosigmoidal approach and adjuvant radiotherapy was used subsequently. The patient remains well 18 months after treatment, with no evidence of recurrence on repeat MRI. The rapid evolution of symptoms involving the Vth, VIIth or VIIIth cranial nerve, or multiple cranial nerves, is suggestive of a malignant lesion of the cerebellopontine angle and/or internal auditory canal. A previous history of neoplasm is important due to the possibility of a metastasis. Cerebellopontine angle metastasis can be found many years after the initial diagnosis of breast neoplasm. Surgery and adjuvant radiotherapy seems to be a good choice for the treatment of patients with this specific type of metastasis.