Perineural spread in head and neck skin cancer.

Perineural spread (PNS) in the head and neck is an infrequent but aggressive manifestation of skin cancer. As such, it can provide access to the intracranial cavity. Squamous cell carcinoma is the most common histology with the facial and trigeminal nerves most often involved. Orbital invasion is an uncommon but devastating result of PNS located around the orbit, particularly the forehead. Diagnosis can be difficult and initial investigations are often unhelpful. Treatment should ideally be directed at preventing further spread before it develops. Adjuvant radiotherapy is often recommended. The disease may present at an advanced state within the orbit or parotid gland or even within the intracranial cavity. Clinicians need to be aware of the potential for PNS because a group of these patients will die from this potentially preventable and treatable form of metastatic skin cancer.