Comparative cytogenetic studies of benign, borderline, and malignant epithelial ovarian tumors

Comparative cytogenetic studies were performed in 40 cases of untreated epithelial ovarian tumors. Of these 40 tumors, 13 were classified as benign, 3 as borderline, and 24 as malignant, according to the WHO classification for ovarian tumors. Of 13 benign ovarian tumors, 4 (30.8%) showed chromosomal abnormalities. Of 4 ovarian tumors, 3 (75%) had single chromosomal abnormalities, and the remaining tumor (25%) retained multiple chromosomal abnormalities. Of 3 borderline-malignant ovarian tumors, 2 (66.7%) showed chromosomal abnormalities. Of 2 ovarian tumors, 1 (50%) indicated single chromosomal abnormalities, and the remaining tumor (50%) revealed multiple chromosomal abnormalities. Of 24 malignant ovarian tumors, 20 (83.3%) showed chromosomal abnormalities. Of these 20 ovarian tumors, 3 (15%) had single chromosomal abnormalities, and the other 17 (85%) exhibited multiple chromosomal abnormalities. These data indicate that the rate of chromosomal abnormalities, especially multiple abnormalities, increases following the progression of malignancy in epithelial ovarian tumors.