Abstract
Twelve patients with cutaneous squamous cell carcinoma had histological perineural invasion. Such invasion was related to an unfavorable prognosis and an aggressive course. Local recurrences secondary to perineural invasion may arise even in cases with primary tumors of smaller size. The possibility of perineural invasion should be considered in squamous cell carcinoma on the head and neck, because intensive local treatment may improve the prognosis. Careful microscopic examinations should be done to avoid overlooking perineural invasion.
