GENOTYPIC ANALYSIS OF PRIMARY HEAD AND NECK SQUAMOUS CARCINOMA BY COMBINED FLUORESCENCE IN-SITU HYBRIDIZATION AND DNA FLOW-CYTOMETRY

Concurrent DNA now cytometric (FCM) and fluorescence in situ hybridiza tion (FISH) analyses were prospectively performed on 24 primary untrea ted head and neck squamous carcinomas for characterization of the geno typic and phenotypic DNA aberrations of these neoplasms. Eleven tumors (42.0%) manifested DNA diploidy (DI = 1.00) and 15 (58.0%) had DNA an euploidy (DI < or > 1.00) by FCM. Fluorescence in situ hybridization r esults showed aneusomy in the majority of DNA diploid and in all DNA a neuploid tumors. The extent of the abnormalities for individual chromo somes and the number of involved chromosomes in a given DNA diploid or aneuploid tumor were significantly different. Overall, a statistical correlation between the FCM DNA index (DI) and the magnitude of the ch romosomal aberration by FISH was found. Our results also show a signif icant association between the DI and histologic differentiation and st age of disease in these neoplasms. In conclusion, (1) chromosomal aneu somy characterizes most DNA diploid (DI = 1.00) and all DNA aneuploid (DI < or > 1.00) head and neck squamous carcinomas; (2) polysomy is th e most prevalent finding; (3) loss of the Y chromosome in tumors from male patients is a consistent feature; (4) the FCM DI reflects net chr omosomal gains or losses in these neoplasms; and (5) DNA aneuploidy is associated with tumor aggressiveness.