JAZF1, YWHAE, and BCOR Gene Translocation in Primary Extrauterine Low-Grade and High-Grade Endometrial Stromal Sarcomas.
AIMS
JAZF1 gene translocation is the most common genetic change in low-grade endometrial stromal sarcoma (LG-ESS) , and YWHAE and BCOR gene translocations are common in high-grade ESS (HG-ESS). Primary extrauterine ESS is rare and there are limited data on molecular alterations in these tumors.


METHODS AND RESULTS
Cases of Primary extrauterine ESS including 8 LG-ESS and 5 HG-ESS were collected. Hematoxylin and eosin (H&E) and immunohistochemistry staining were used to observe histomorphology and analyze related proteins expression. JAZF1, YWHAE, and BCOR gene rearrangements were explored using fluorescence in-situ hybridization (FISH). In LG-ESS, the tumor cells resembled normal proliferative-phase endometrial stromal cells; CD10, ER, and PR were expressed in all 8 samples. In HG-ESS, the tumor cells consisted of uniform high-grade round and/or spindle morphology, sometimes with a low-grade component; CD10 was fully expressed in 1 case and focally expressed in 4 cases; BCOR was expressed in all 5 samples and Cyclin D1 in 4 of 5 cases. FISH analysis showed JAZF1 gene translocation occurred in 1 of 8 LG-ESS cases(12.5%). YWHAE gene translocation occurred in 4 of 5 HG-ESS cases, with a positive rate of 80%. BCOR gene translocation was negative in all 5 cases.


CONCLUSIONS
In extrauterine LG-ESS, the positive rate of JAZF1 gene rearrangement was significantly lower than in uterine LG-ESS. This result limited the value of JAZF1 gene translocation for diagnosis. YWHAE gene rearrangement is a common genetic change in extrauterine HG-ESS. Further studies are required to confirm these findings, especially in LG-ESS.
['Sun|Lili|L|', 'Zhao|Wei|W|', 'Zhao|Zehua|Z|', 'Zhu|Yanmei|Y|']
JAZF1 YWHAE BCOR fluorescence in-situ hybridization extrauterine endometrial stromal sarcoma