Genomic characterization of endometrial stromal sarcomas with array comparative genomic hybridization

- We analyze endometrial stromal sarcoma (ESS) and benign endometrial stromal nodule (ESN) samples.
- We investigate common genetic alterations in ESS and ESN samples by comparative genomic hybridization (aCGH).
- Thereby we aim to show whether a linear tumor progression from ESN to ESS is likely or not.
- Copy number changes (CNCs) increase from ESN to low-grade ESS and to undifferentiated endometrial sarcoma (UES).
- A linear tumor progression from ESN to low-grade ESS and to UES seems to be unlikely.

IntroductionThe endometrial stromal sarcoma (ESS) is a very rare uterine sarcoma, counting for 1-3% of all gynecologic malignancies. ESS represents 0.2-8% of all uterine malignant tumors and accounts for about 10% of all uterine sarcomas. With regard to chromosomal aberrations, very little is known about benign and malignant endometrial stromal tumors.Methods30 tumors, consisting of 4 cases of benign endometrial stromal nodule (ESN), 22 cases of low-grade ESS and 4 cases of undifferentiated endometrial sarcoma (UES), were analyzed by array-comparative genomic hybridization (aCGH).ResultsESN did not show many copy number changes (CNCs) by aCGH. Frequent losses could be identified on chromosomes 7p and 19, and gains on chromosomes 1q, 6p and 8q. Low-grade ESS presented as a very heterogeneous group. 90% (20/22) of cases displayed aberrations. Most frequent changes were losses on chromosomes 7 and 22, and gains on chromosome 1q or 11. UES showed a high number of chromosomal aberrations and on every chromosome CNCs were detected. Most frequent changes were losses on chromosomes 1q, 2q (3/4, 75%) and 13, and gains on chromosomes 1q and 17p.ConclusionOur data shows an increasing number of CNCs from ESN to low-grade ESS and to UES. However, the chromosomal aberrations differ considerably between the investigated ESN-, low-grade ESS- and UES cases and thus, a linear tumor progression seems to be unlikely.