Detection of numerical chromosomal abnormalities in epithelial ovarian neoplasms by fluorescence in situ hybridization (FISH) and a review of the current literature.

Preliminary retrospective chromosomal analysis was performed using fluorescence in situ hybridization (FISH) with alphoid DNA probes for chromosomes 1, 3, 6, 8, 12, 17, and X. Twenty-four epithelial ovarian tumors were examined in this pilot study, including 8 borderline (LMP) serous tumors, 9 serous carcinoma, and 7 mucinous carcinoma. Hybridization signals were counted to demonstrate the frequency of aneusomy, trace chromosomal progression, and identify the predominance of chromosome copy number abnormalities that are specific to a particular histotype. The preliminary results revealed almost an equal number of mean aneusomies in serous (58.13 +/- 13%) and mucinous (64.33 +/- 10%) carcinoma, both of which were slightly higher than borderline serous tumors (50.57 +/- 17%). Hyposomies 3 and X were significantly higher in mucinous than in serous ovarian carcinomas, and lowest in borderline serous tumors (P<0.05 and P<0.01). Signal losses were a more frequent abnormality in all three histologic subtypes. Mucinous carcinomas showed a loss of chromosomes 8 (45.00 +/- 28%) and 3 (43.14 +/- 16%), in addition to a loss of chromosome X (56.29 +/- 12%). Serous carcinomas showed a gain of chromosome 1 (39.44 +/- 32%), followed by losses of chromosomes 6 (37.00 +/- 20%), 17 (36.44 +/- 19%), and 8 (36.89 +/- 19%). In borderline serous tumors, the most frequent findings were losses of chromosomes 6 (38.00 +/- 17%), 12 (36.88 +/- 17%), and 3 (36.13 +/- 21%). However, further research is necessary to substantiate these preliminary results and elucidate their clinical significance. A brief review of the literature pertaining to interphase cytogenetics in ovarian epithelial tumors is discussed also.