Uterine Leiomyomas: Histopathologic Features, MR Imaging Findings, Differential Diagnosis, and Treatment

Abstract

Leiomyomas are the most common uterine neoplasm and are composed of smooth muscle with varying amounts of fibrous connective tissue. As leiomyomas enlarge, they may outgrow their blood supply, resulting in various types of degeneration: hyaline or myxoid degeneration, calcification, cystic degeneration, and red degeneration. Leiomyomas are classified as submucosal, intramural, or subserosal; the latter may become pedunculated and simulate ovarian neoplasms. Although most leiomyomas are asymptomatic, patients may present with abnormal uterine bleeding, pressure on adjacent organs, pain, infertility, or a palpable abdominalpelvic mass. Magnetic resonance (MR) imaging is the most accurate imaging technique for detection and localization of leiomyomas. On T2-weighted images, nondegenerated leiomyomas appear as well-circumscribed masses of decreased signal intensity; however, cellular leiomyomas can have relatively higher signal intensity on T2-weighted images and demonstrate enhancement on contrast material-enhanced images. Degenerated leiomyomas have variable appearances on T2-weighted images and contrast-enhanced images. The differential diagnosis of leiomyomas includes adenomyosis, solid adnexal mass, focal myometrial contraction, and uterine leiomyosarcoma. For patients with symptoms, medical or surgical treatment may be indicated. MR imaging also has a role in treatment of leiomyomas by assisting in surgical planning and monitoring the response to medical therapy.

Obstetric MRI

“…Fibroids undergoing hemorrhagic degeneration during pregnancy typically demonstrate diffuse or peripheral high signal intensity on T 1 -weighted imaging and variable signal intensity on T 2 -weighted imaging (32). Edema can cause diffuse increased signal intensity of uterine fibroids on T 2 -weighted imaging and may antedate degeneration (33).…”

The contribution of Magnetic Resonance Imaging in the differential diagnosis between leiomyoma typical, atypical and uterine sarcomas: Personal experience

“…Leiomyomas are classified in submucosal, intramural and subserosal; these last ones can be pedunculate and in some cases simulate an ovarian malignancy. Although the leiomyomas are asymptomatic in most of cases, the presence of one or more submucosal fibroids can determine menometrorrhagia or be an obstacle to reproduction (greater rate of abortions); less frequently the presence of very large leiomyomas may be linked to pressure symptoms on the surrounding structures or to abdominal pain [2,3] .…”

“…On T2 images typical leiomyomas appear as circumscribed hypointense masses compared to myometrium [2] , while sarcomas appear as large iso-hyperintense masses. The same appearance is shown by cellular leiomyomas and some types of degenerated leiomyomas, which then may mime sarcomas.…”

An unusual presentation of a severely calcified subserous leiomyoma in a postmenopausal woman: a case report

“…As leiomyomas enlarge, they may outgrow their blood supply, resulting in various types of degeneration: hyaline or myxoid degeneration, calcification, cystic degeneration, or red degeneration. 5 In general, hyaline degeneration is the most common (63%) form of degeneration, while the others occur less frequently, such as myxomatous changes (13%), calcification (8%), mucoid changes (6%), cystic degeneration (4%), red degeneration (3%), and fatty changes (3%). 6 Calcified degeneration commonly seen in menopausal age group, black women and in women who have pedunculated subserous tumour.…”