Cutaneous squamous cell carcinoma with perineural invasion: a case report and review of the literature.

Perineural invasion (PNI) is an uncommon manifestation of cutaneous squamous cell carcinoma (SCC). We report a case of recurrent cutaneous SCC with PNI diagnosed both clinically and histologically. We also provide a review the literature. Clinicians should be aware of this uncommon finding, as PNI has been associated with increased local recurrence, local and distant metastasis, and poor prognosis. Patients with clinical findings associated with perineural involvement have a poorer prognosis than those incidentally discovered on histologic examination, which emphasizes the importance of a thorough history and neurologic examination in patients with cutaneous SCC to identify those who will require more aggressive therapy.