Karyotypic abnormalities of squamous cell carcinoma of the oral cavity

The karyotypic abnormalities in 18 squamous cell carcinomas of the oral cavity were studied in unbanded chromosomes on direct preparations of the tumor material. The chromosome counts revealed a great variability in the number of chromosomes per cell of each tumor, the range being from 31 to 148 in all cases studied. The modal population of cells was diploid in five cases, triploid in eight cases, tetraploid and pentaploid in one case each. Reduction of the number of chromosomes was more consistently observed in groups A and B, frequently involving chromosome No 1 and increases in groups C, D, E, F and G. Markers were frequently present, the most common being an almost metacentric chromosome of the size of the chromosomes of Group C.