Leiomyomas Uterine leiomyomas are benign tumors composed of smooth muscle and fibrous connective tissue. They are also referred to as fibromyomas, fibromas, fibroleiomyomas, fibroids or simply myomas. They may occur singly but often are multiple, with variations in size and are more common in African-American than in white women. It's believed that myomas are monoclonal tumors resulting from somatic mutations of one single neoplastic cell. The activity of this enzyme is reduced in myomatous tissue, which has also more receptors for estrogen than normal myometrium.
Progesterone is the natural antagonist of estrogen.
They grow out toward the peritoneal cavity,and can be sessile or pedunculated. The pedunculated ones may attach themselves to adjacent structures like the bowel, omentum or mesentery, and develop a secondary blood supply, loosing its primary uterine blood supply - parasitic leiomyoma. Subserous myomas may also extend into the broad ligament- intraligametary leiomyomas. They can be sessile or pedunculated. The pedunculated myomas can protrude to or through the cervical canal, and on these cases they are more subject to torsion or infection.