Syphilitic Chancre of the Lip.

Syphilis is a sexually transmitted disease caused by Treponema pallidum. The primary stage of the disease (the chancre) mainly involves the genital areas. Extragenital areas are involved in 5%-14% of cases, many of which occur in the oral cavity. Among the extragenital locations, the lip is the most frequent; however, despite this, published cases of the chancre of the lip are few. We present a case of a chancre presenting on the lip of a nonimmunocompromised 55-year-old male patient with immunohistochemical confirmation.