Detection of DNA gains and losses in primary endometrial carcinomas by comparative genomic hybridization

Comparative genomic hybridization (CGH) was used in a retrospective analysis of chromosomal imbalances in frozen primary tumor specimens from 14 endometrial carcinoma patients. Chromosome changes were detected in nine cases (64%), and tumor stage and grade tended to parallel the degree of genomic imbalances. Gain of the entire long arm of chromosome 1 was observed in six cases (43%), three of which displayed only this chromosome change. Other common sites of copy number increases included 8q21 → qter (4 cases), 10p15 (4 cases), 10q11 → q24 (3 cases), and 13q21 → qter (3 cases, each with stage III disease). Two of the tumors with gains of chromosome 10 involved the whole chromosome, and this was the sole abnormality in one case. DNA amplification at 5p14 → p15 was identified in one specimen, a stage III tumor having numerous imbalances. DNA microsatellite analysis revealed multiple replication errors (RER), indicative of the RER⁺ phenotype, in four of 13 (31%) cases evaluated. The RER⁺ phenotype was observed in four of six stage 1a tumors but in none of seven stage Ib or stage III tumors. Multiple genomic imbalances detected by CGH were not observed in RER⁺ tumors but were detected in five of nine tumors without the RER⁺ phenotype. These investigations demonstrate the feasibility of CGH for the retrospective assessment of chromosomal changes in endometrial carcinoma specimens. Moreover, these data suggest that the etiologies in tumors with and without the RER⁺ phenotype may differ.