Nachweis von TP53-Mutationen mittels Exfoliativzytologie (brush biopsy) oraler Leukoplakien

Objective. The aim of this study was to determine the prevalence of mutations of the tumour suppressor gene TP53 in oral leukoplakias. Material and method. Brush biopsy specimens of 43 oral leukoplakias, 26 oral squamous cell carcinomas (OSCC) for reference, and the oral mucosa of 4 clinically normal volunteers were collected. DNA of the critical exons 5–8 was analysed by temperature gradient gel electrophoresis (TGGE). Results. The prevalence of mutations was 57.7% in OSCC, 39.5% in leukoplakias and 0% in controls. The highest frequency of mutations was found in exon 5 (46.2%) in OSCC and in exon 6 (23.3%) in leukoplakia. More than one mutation was detected in 26.9% of OSCC and 7% of leukoplakia specimens. At least one mutation was found in 37.5% of T1 OSCC and 100% of T4 OSCC specimens and in 37.1% of the L1 leukoplakia and 100% of L3 leukoplakia specimens. Conclusions. TP53 mutations could be a useful prognostic indicator in precancerous oral lesions. Although the brush biopsy technique appears simple clinically, further investigations are necessary to specify the implications of genetic analysis.