Noninvasive detection of aneuploid cells in laryngeal epithelial precursor lesions

BACKGROUND: Most cases of laryngeal cancer are preceded by precursor lesions which, if left untreated, can progress toward an invasive cancer. The objective of this study was to investigate the presence of chromosomal numerical aberrations in cells that were collected by noninvasive brush sampling from laryngeal lesions. METHODS: Laryngeal brush samples from 52 patients were analyzed simultaneously for morphology and fluorescence in situ hybridization (FISH) using centromeric probes for chromosome 17, chromosome 8, and a locus-specific instability (LSI) v-myc avian myelocytomatosis viral oncogene homolog (myc) proto-oncogene protein (C-MYC) probe for the MYC gene. The patients were divided according to histopathologic diagnosis. Group 1 included patients with squamous cell carcinoma, carcinoma in situ, and severe dysplasia; Group 2 included patients with moderate dysplasia, mild dysplasia, and hyperplasia; and Group 3 included patients with benign nondysplastic lesions. RESULTS: The proportion of cells with MYC and chromosome 8 gains demonstrated significant trends toward being the highest in Group 1 and the lowest in Group 3 (P = .001 and P = .003, respectively). No significant trend was observed for chromosome 17. Mann-Whitney Bonferroni-corrected analyses revealed that the most significant contribution was the difference between Groups 1 and 3 (P = .0195 for MYC gains and P = .036 for chromosome 8 gains). When using a cutoff point of 4% aneuploid cells (ACs), both MYC and chromosome 8 differed significantly between groups (P = .030 and P = .037, respectively). CONCLUSIONS: The current results suggested that FISH analysis of brush samples obtained noninvasively from suspicious laryngeal lesions can augment the clinical examination in predicting the nature of the lesions and can aid clinicians in monitoring and followup of high-risk patients.