Odontogenic myxomas lack PDGFRB mutations reported in myofibromas

The molecular pathogenesis of odontogenic myxoma has not been established yet. Considering that odontogenic myxoma may show myofibroblastic differentiation and myxoid areas can be observed in intra-osseous myofibromas, we tested the hypothesis whether both tumors share a common molecular profile. As recent studies have reported PDGFRB recurrent driver mutations in myofibroma, we evaluated PDGFRB mutations in odontogenic myxomas.

A convenience sample of 15 odontogenic myxomas cases was selected. We direct sequenced PDGFRB exons 12 and 14, where p.R561C (c.1681C>T) and p.N666K (c.1998C>G) hotspot mutations have been reported among others in single and/or multiple myofibromas.

All 15 odontogenic myxoma samples were successfully sequenced, and all 15 had wild-type sequences for the PDGFRB mutations investigated.

Our findings suggest that PDGFRB mutations do not play a role in odontogenic myxoma pathogenesis, which might be helpful in the differential diagnosis of challenging cases.