Primary ovarian CIC-rearranged sarcoma in a child: A rare case report and review of the literature

Liqin KeLili LiuYing WuYun SunYongjiao WangJiahui XiaWen zhang^*

• Department of Pathology, Wuhan Children’s Hospital, Wuhan, China

Introduction: CIC-rearranged sarcoma (CRS) is a rare type of high-grade undifferentiated small round cell sarcoma characterized by a spectrum of possible CIC gene rearrangements. It arises predominantly in the deep soft tissues of the limbs and trunk in young individuals (total range, 0.5-83 years; mean, 27-37 years; median, 24.5-33 years), and less commonly in bone and viscera. The cases occurring in the female reproductive tract are very rare, it has not yet been described in the ovary. Case presentation: We report a CRS case that arose from the left ovary in a 5‑year-old girl. Histologically, the tumor was lobulated or leaf shaped with a fibrotic septum, composed of closely arranged small‑ to medium‑sized round cells and short spindle shaped cells. And the neoplastic cells exhibited multifocal membrane positivity for CD99 and diffuse positivity for WT1, TLE1, FLI‑1, P53, INI-1, and Calretinin, CD56 focal positive, while it was negative for ETV4. Fluorescent in situ hybridization analysis showed CIC-positive split signals. Conclusion: CIC-rearranged sarcomas are highly aggressive tumors. Rare CRS have been reported in the female genital tract and its diagnosis is very difficult. Especially for cases with atypical morphology and immunohistochemistry, it is necessary to integrate molecular features in the diagnosis of undifferentiated neoplasms.