MYometrial Lesion UltrasouNd And mRi

INTRODUCTION

Uterine sarcomas are rare malignant tumors arising from the mesenchymal tissues of the uterus including the endometrial stroma, uterine muscle and connective tissue. They represent 1% of female genital tract malignancies and 3-7% of all uterine malignances with a worldwide annual incidence of 1.55-1.95 per 100.000 women. Malignant mesenchimal tumors include: uterine leiomyosarcoma (LMS), endometrial stromal sarcoma (ESS), and undifferentiated uterine sarcoma (UUS), and other (eg adenosarcoma, epithelioid sarcoma, STUMP). The current WHO classification also includes a smooth muscle tumor with features that preclude an unequivocal diagnosis of leiomyosarcoma, but do not fulfill the criteria for leiomyoma, or its variants, therefore is defined as smooth uterine muscle of uncertain malignant potential (STUMP). While most STUMP patients have good outcomes, unexpected aggressive behavior can be seen in some of the tumors.

The mean age at diagnosis is approximately 60 years old. However, uterine sarcomas have been diagnosed in women as young as 20 years old . The prevalence of sarcoma in women undergoing hysterectomy or myomectomy for a myometrial mass, is approximately 0.001 percent (1 in 1000) (Parker 94), with a range from 0.005 (1 in 2000) to 0.28 percent (1 in 352). , The discrimination between benign and malignant myometrial lesions is clinically relevant to plan the optimal management (surgery versus medical treatment) and to define the most appropriate surgical approach.

However, the diagnosis of uterine sarcomas or STUMP is a challenge and no validated clinical or radiological criteria can accurately distinguish benign from malignant myometrial tumors.

In particular, data on the ultrasound features of uterine sarcomas are scarce and they are mainly based on retrospective case series. The role of CT(Computed Tomography) has generally been limited to identify extrauterine disease, including local spread within the pelvis and metastatic disease. MRI (Magnetic Resonance Imaging) )represents an accurate diagnostic imaging modality in the assessment of gynecological pathologies with high soft tissue contrast, large field-of-view and multiplanar imaging capabilities; however, no accurate diagnostic criteria have been validated to discriminate between benign and malignant myometrial lesions.