endometrial stromal tumor (MONDO_0003311) is neoplasms of the endometrial stroma that sometimes involve the myometrium. These tumors contain cells that may closely or remotely resemble the normal stromal cells. Endometrial stromal neoplasms are divided into three categories: (1) benign stromal nodules; (2) low-grade stromal sarcoma, or endolymphatic stromal myosis; and (3) malignant endometrial stromal sarcoma (sarcoma, endometrial stromal). Also known as: endometrial stroma neoplasm, endometrial stroma tumor, endometrial stroma tumour, endometrial stromal neoplasm, endometrial stromal tumor (morphologic abnormality), endometrial stromal tumour (morphologic abnormality), neoplasm of endometrial stroma, tumor of endometrial stroma.