Sushila Ladumor, MD


 Endometrial stromal sarcoma (ESS) is a rare malignant tumor of the  endometrium, occurring in the age group of 40-50 years.




 50 year old female patient with menorrhagia, lower abdominal pain and heaviness.
 On examination, found to have large abdominal pelvic mass.
 US done and shows large mass inseparable from uterus with some vascularity.

 Large lobulated mass inseparable from fundus of uterus and shows heterogenous  enhancement with lots of vascularity around mass, more at anterior margin. Few  small low density areas within mass representing cystic degeneration. Few small  nodules around the large mass and are completely separate from the mass. The  mass is causing compression over pelvis colon. The endometrium is clearly  visible. The lesion appears to be solid. Rest of the exam within normal limit.




 The differential diagnosis of a relatively hypervascular, soft-tissue mass  arising from the apex of the uterus includes, large subserosal fibrod, or a  primary malignancy of the uterus (such as leiomyosarcoma).




 A total hysterectomy with was performed along with resection of surrounding  nodules, omentum and colonic mucosa. The pathological findings were leading to  the diagnosis of endometrial stromal sarcoma. This tumor does not involve the  ovaries or fallopian tubes. Lymphovascular invasion was there. Extensive  involvement of colonic wall with unremarkable colonic mucosa. Extemsive omental  involvement and nodule was positive for deposit.




 Uterine sarcomas represent 2-5% of all uterine malignancies. There are three  types: carcinosarcoma (also known as mixed mullerian tumor) is the most common,  leiomyosarcoma is next, and endometrial stromal sarcoma (ESS) is the least  common (<10% of uterine sarcomas). Endometrial stromal sarcomas are composed of  cells that are identical to or closely resemble normal proliferative-phase  endometrial stromal cells. These tumors may arise from the endometrium but can  also be seen in the setting of adenomyosis or endometriosis.

 Endometrial stromal sarcoma typically occurs in women between the ages of 42  and 59 years. Symptoms include abnormal uterine bleeding and pain. Risk factors  are fairly nonspecific and include prior pelvic radiation therapy, age, and race  (slightly higher incidence among blacks). There may also be hormonal factors,  though this is not well understood. The differential diagnosis for ESS includes  leiomyoma with cystic degeneration, leiomyosarcoma, and endometrial carcinoma.  The subtle differences between these entities are best demonstrated with MRI.

 On MR, endometrial stromal sarcomas appear as large tumors in the endometrial  cavity and/or myometrium. The signal is typically high on T1-weighted images and  heterogeneously high on T2-weighted images. The tumor margins are typically  irregular, often with marginal nodular lesions. Intramyometrial worm-like  nodular extensions may be visible. Hemorrhage and necrosis are common. Most ESS  show greater enhancement than normal myometrium. Overall, ESS are difficult to  differentiate from leiomyomas with cystic degeneration, leiomyosarcomas, and  endometrial carcinomas.

 There are, however, several imaging features that differentiate ESS from  those other tumors. Endometrial carcinomas typically do not display irregular  marginal lesions, marginal nodules or intramyometrial nodules. The avid  enhancement pattern of ESS (relative to the myometrium) is also not typical for  endometrial carcinomas. Leiomyomas and leiomyosarcomas generally do not have the  high T2 signal that is characteristic of ESS. In addition, these tumors display  a different pattern of enhancement; markedly increased signal after contrast is  unusual. Finally, leiomyomas typically do not have irregular margins with small  nodules (though these features may be seen in leiomyosarcomas).



Articles

Endometrial stromal sarcoma (ESS) is a rare malignant tumor of the endometrium, occurring in the age group of 40-50 years.

Author | Sushila Ladumor, MD

Articles

Endometrial Stromal Sarcoma