Ovarian Sclerosing Stromal Tumor. Spectrum of Ultrasound Findings. A Case Report and Review of Literature

We present a case of a very rare benign ovarian tumor, a sclerosing stromal tumor (SST). In addition, we performed a review of the literature to describe the spectrum of sonographic findings of this tumor. Our case was a 43 year-old woman, referred for pelvic endometriosis evaluation. Transvaginal ultrasound showed a solid tumor with a maximum diameter of 30 mm arising from external pole of the right ovary. Color Doppler assessment showed a moderate/abundant vascularity. A diagnosis of presumed ovarian surface serous borderline tumor was established. Surgery was performed with tumor removal. Definitive histological diagnosis was benign sclerosing stromal ovarian tumor. In the literature review, we identified 81 cases describing sonographic findings of this tumor. This spectrum was wide, with most tumors reported as purely solid or predominantly solid with cystic areas (86.7%) and few cases were reported as multilocular-solid, unilocular-solid, multilocular and unilocular. Echogenicity was heterogeneous in 96.9% of the cases. When vascularity was described, 61% of the cases had moderate/abundant vascularization. Calcification and shadowing were rare. Ascites was reported in 16.0% of the cases. In conclusion, the spectrum of findings of SSTs may vary, but most cases were solid tumors. Our case fits this pattern.