Aneuploidy - an early event in the malignant transformation process of oral lichen planus. A molecular cytogenetic study

Objectives: Oral lichen planus (OLP) carry an increased risk for malignant transformation. The aims of the study were to follow-up OLP patients (OLPp) and to detect aneuploid cells in samples collected by brush samples from the oral mucosa.
Methods: OLPp were followed and repeated brush samples were simultaneously analyzed for morphology and fluorescent-in-situ-hybridization (FISH) using centromeric probes for chromosomes 2 and 8
Results: 127 patients with OLP and 45 control subjects were analyzed. Aneuploid cells were found in 38 patients (29.9%); in 8 (6.3%) over 5% of the cells were aneuploid. Aneuploid cells were also detected in the normal looking mucosa in 10 patients. Three patients developed oral cancer within an average follow-up period of 32 months; over 10% of the cells examined in these patients were aneuploid.
Conclusions: OLP carry an increased risk for chromosomal instability and can be viewed as a widespread pre-malignant disease. FISH analysis of brush samples obtained non-invasively from OLPp can augment the clinical examination in evaluating the nature of the disease process predicting the malignant potential