Basal cell carcinoma of the buccal mucosa in a patient with nevoid basal cell carcinoma syndrome.

Basal cell carcinoma (BCC) of the oral cavity is a controversial lesion with clinical and histopathologic features that overlap with those of peripheral ameloblastoma (PA). Ber-EP4, a cell surface glycoprotein preferentially expressed in BCC of the skin, has been suggested as a useful marker to support the diagnosis of oral BCC.This study presents a case of intraoral BCC arising in the anterior buccal mucosa of a patient with nevoid basal cell carcinoma syndrome (NBCCS), which represents a previously unreported clinical finding, to our knowledge. Histopathologic and immunohistochemical features of the case were compared to examples of PA, conventional intraosseous ameloblastoma, sporadic cutaneous BCC and cutaneous BCC from NBCCS patients. Ber-EP4 expression by the oral tumor was distinct from both peripheral and intraosseous forms of ameloblastoma and was identical to cutaneous BCC in both sporadic and syndromic settings.