[The problem of the ploidy reduction in carcinogenesis of the uterine cervix: numerical chromosome anomalies in carcinoma in situ (author's transl)].

The authors report on cytogenetic studies of the uterine cervix in 11 carcinoma in situ. In six cases with intact epithelium the cells were no longer normal and five cases showed beginning stroma invasion. The numerical chromosome anomalies observed indicate the presence of ploidy reduction. In accord with cytogenetic findings in precancerous conditions and in carcinoma of the uterine cervix published in the literature, the ploidy reduction may be regarded as a probable causal principle for malignancy at the uterine cervix.