CyberKnife radiosurgery for management of intracranial perineural spread of cutaneous malignancies.

Intracranial perineural spread (PNS) is a rare complication of cutaneous malignancies and refers to access of the tumor to the intracranial space typically by tracking along cranial nerves. Patients are usually treated with palliative external-beam radiotherapy or with radiosurgery if there has been prior standard radiotherapy. Two patients are presented, both with cranial neuropathies occurring years after treatment for cutaneous malignancies. Radiographic workup showed recurrent tumor involving multiple cranial nerves. Both patients were treated with CyberKnife radiosurgery. To the author's knowledge, these are the first reported patients with intracranial PNS treated via CyberKnife radiosurgery.