Ameloblastoma: a neglected criterion for nevoid basal cell carcinoma (Gorlin) syndrome

Ameloblastomas are considered to be aggressive and locally invasive neoplasms derived from odontogenic epithelium with a tendency for recurrence and bone destruction. Although the relationship between nevoid basal cell carcinoma syndrome (NBCCS) and ameloblastoma is less frequent, it might constitute a peculiar stigmata of this hereditary disorder. The objective of the current study was to evaluate whether a combined clinical and biomolecular approach could be useful for the identification of NBCCS among patients with a diagnosis of ameloblastoma. The authors collected ameloblastoma tumors recorded in the databases of the Pathology Departments of the University of Modena during the period 1991-2011. Family trees were drawn for all 41 patients affected by these specific odontogenic tumors. Two patients with ameloblastoma were also affected by multiple basal cell carcinomas and odontogenic keratocysts tumors (OKCTs) achieving the requested clinical criteria for the diagnosis of NBCCS. The clinical diagnoses were confirmed by the identification of two different novel PTCH1 germline mutations (c.2186A > T [p.K729 M]; c.931insA) in those unrelated patients. Clinical ameloblastoma findings can be used as screening for the identification of families at risk of NBCCS. Ameloblastomas diagnosis warrants the search for associated cutaneous basal cell carcinomas and other benign and malignant tumors related to NBCCS. Thus, we propose the inclusion of ameloblasoma as criterion for the identification of NBCCS.