High negative prediction for the Basel sarcoma score: Sonographic assessment of features suspicious of uterine sarcoma

•The Basel-Sarcoma-Score (BSS) is a valuable tool in the preoperative distinction of myoma from uterine sarcoma.•BSS is simple and has high NPV: minimally invasive surgery can be discussed if BSS is negative.•Using a threshold of >1 as cut-off for malignancy showed the best overall test performance.•BSS improves patient counseling and allows for choosing the best surgical procedure.•BSS underscores the value of standardized ultrasound in patients referred for surgery in gynecological oncology.