Differentiating uterine adenosarcoma from endometrial polyps: MRI imaging features

Area of Science:

• Gynecologic Oncology
• Radiology
• Pathology

Background:

• Uterine adenosarcoma is a rare malignancy requiring accurate preoperative differentiation from benign endometrial polyps.
• Sarcomatous overgrowth (SO) is a pathological feature associated with poor prognosis in uterine adenosarcoma.

Purpose of the Study:

• To identify magnetic resonance imaging (MRI) features that distinguish uterine adenosarcoma from endometrial polyps.
• To assess MRI's ability to predict the presence or absence of sarcomatous overgrowth (SO) in uterine adenosarcoma.

Main Methods:

• A multicenter retrospective study analyzed 11 uterine adenosarcomas (5 with SO, 6 without) and 20 large endometrial polyps (≥3 cm).
• Quantitative MRI parameters (volume, cystic lesion size, DWI signal ratio, ADC, normalized ADC) and qualitative features (hemorrhage, signal intensity, enhancement) were evaluated.
• Comparisons were made between uterine adenosarcoma and endometrial polyps, and between SO and non-SO uterine adenosarcoma subgroups.

Main Results:

• Uterine adenosarcomas exhibited significantly larger tumor volumes, larger cystic lesions, higher DWI signal ratios, and lower ADC/normalized ADC values compared to endometrial polyps.
• Gross hemorrhage and high DWI signal intensity were more frequent in uterine adenosarcomas.
• No significant MRI differences were found between uterine adenosarcomas with and without SO.

Conclusions:

• Key MRI features for differentiating uterine adenosarcoma from endometrial polyps include larger tumor volume, larger cystic lesions, intratumoral hemorrhage, higher DWI signal intensity, and lower ADC values.
• These imaging findings can assist in the preoperative distinction between these uterine lesions.