Ameloblastic carcinoma and metastasizing ameloblastoma are rare tumors of odontogenic origin. While ameloblastic carcinoma exhibits microscopic features of malignancy, regardless of the presence of metastasis, metastasizing ameloblastoma is a microscopically benign tumor, which, however, possesses the potential to metastasize. Here, we present a case of a young man with recurrent and, later, metastasizing, mandibular lesion, the definitive diagnosis of which remains (despite extensive genotyping of the original tumor, recurrent lesion and metastases) uncertain. Our histopathological analyses uncovered a metastasizing tumor with features of ameloblastic carcinoma that has developed from ameloblastoma. We use this case to illustrate the similarities and differences between these two types of tumors and the difficulty in their distinguishing. First, we analyzed gene expression of WNT signaling pathway members in sample collected from this patient as multiple molecules from this pathway are involved in establishing of cell polarity and cell migration important for epithelial-mesenchymal transformation during tumor metastasizing. We found upregulation of several cell migration genes. Moreover, we performed sequencing of the primary tumor as well as lung metastases using the most common panel for cancer mutation analyses and uncovered mutations BRAF p.V600E and FANCA p.S858R in both tumor and the metastasis. In conclusion, our case study describes unique case report of ameloblastic tumor, which was associated with BRAF mutation and newly described mutation in FANCA gene. WNT signaling was altered on differentlevels and several members of this signaling pathway uncovered by our analyses should be tested as potential markers of early cellular changes in tumorous tissues. This research was supported by the Czech Ministry of Health (NU20-08-00205).