Chromosomes in preinvasive, microinvasive and invasive cervical carcinoma

The chromosomes in 32 preinvasive, 5 microinvasive, and 10 invasive cervical carcinomas were studied in direct fixations. The chromosome pattern was surveyed in relation to earlier results obtained in this field. Of the preinvasive lesions 66% had a diploid, 13% a triploid and 22% a tetraploid modal population. In 3 of the microinvasive tumours the modal population was diploid and in 2, triploid. In the diploid subgroup of the preinvasive tumours without and with microinvasion the chromosome number 46 was predominant. In the polyploid subgroup all were hypertriploid to hypotetraploid. Of the invasive carcinomas 7 exhibited a diploid modal population and 3 a triploid. The modes were spread throughout the ploidy regions. The normal diploid karyotype was common in carcinoma in situ, but absent in the microinvasive and invasive carcinomas. Gains and losses in the modal population were associated with the same chromosome types in the different stages of malignancy. Chromosomes were usually in excess in group C, and deficits were found in group B and, more often, in groups D and G. Structural aberrations appeared occasionally in preinvasive and microinvasive lesions and more often in invasive tumours, usually as an integrated part of the modal karyotype. A statistical analysis of the mean karyotype deviations in the entire material revealed a non‐random pattern, and a significant increase in the severity of the chromosome changes with degree of malignancy.