OP20.03: Ultrasound features of endometrial stromal sarcomas

Abstract

To describe the ultrasound findings of endometrial stromal sarcomas. This is a retrospective study. Patients with a histological diagnosis of endometrial stromal sarcoma (ESS) who had undergone preoperative ultrasound examination were identified from the databases of 13 tertiary ultrasound centres. The tumours were described by the principal investigator at each contributing centre on the basis of ultrasound images and ultrasound reports using definitions and parameters previously agreed upon in a consensus meeting. We identified 79 women with a histological diagnosis of endometrial stromal sarcomas, 48 of whom (60.8%) had low grade endometrial stromal sarcoma (EES) and 31 (39.2%) undifferentiated endometrial stromal sarcoma (UES). Seven (8.9%) women were asymptomatic (incidental finding), whilst the remaining complained of abnormal vaginal bleeding (62%) and/or abdominal pain and distension. The median largest diameter was 68 mm (range 12-210 mm) for EESs and 70 mm (7-250 mm) for UESs. The tumour appeared heterogeneous in (34/48) 71% of EESs and (24/31) 87% of UESs. Cystic areas with irregular contour were observed in 11/48 (23%) of EESs and in 12/31 (38.7%) of UESs respectively. Irregular border was present in (19/48) 40% of EESs and (23/31) 74% of UESs. In (37/48) 77% of EESs and (23/31) 87% of UESs no shadowing was observed. Most tumours (48/76, 61%) were moderately or very well vascularised whilst 28/76 (36.8%) were minimal or no vascularised on colour or power Doppler ultrasound. Uterine lesion with heterogeneous echotexture, internal irregular cyst areas and no shadowing should raise the suspicion of uterine sarcomas. No substantial differences were observed between EESs and UESs, but a regular border seems to be more common in EESs. The absence of vascularisation within the lesion cannot exclude malignancy.