RESUMEN
BACKGROUND: The purpose of this study was to evaluate loss of heterozygosity (LOH) and to assess BRAF V600E mutation in oral neurofibromas, palisaded encapsulated neuromas (PEN) and schwannomas. METHODS: Six oral neurofibroma, 5 PEN and 3 schwannoma samples were included in the study. LOH was assessed using polymorphic microsatellite markers at chromosome regions 3p (marker D3S1029), 9p (markers D9S171, D9S162, D9S157), 11q (marker D11S1369), and 17p (markers AFM238WF2 and P53), and results were evaluated after capillary electrophoresis. BRAF mutation encoding V600E was assessed by real-time PCR with a specific TaqMan probe to detect the T>A transversion at position c.1799. RESULTS: LOH occurred at chromosomes 3p (marker D3S1029), 11q (D11S1369) and 17p (AFM238WF2 and P53). LOH occurred in 2/6 neurofibromas, 2/5 PEN and in none of the 3 schwannoma samples. The 6 neurofibromas, 2/2 PEN evaluated and the 3 schwannomas were BRAF wild type. CONCLUSION: According to our results, oral benign peripheral nerve sheath tumours have a low LOH rate, but P53 locus alteration is occasionally found. Additionally, BRAF V600E mutation is either not relevant to the molecular pathogenesis of this group of lesions of the oral cavity, or may occur at very low rates.