105: Uterine Leiomyomata

Key Points

• Disease summary:

  • Uterine leiomyomata (UL) are benign tumors of the uterine myometrium.

  • UL are classified by tumor location within the uterus: subserosal, intramural, and submucosal.

  • The prevalence of UL is estimated around 75% for women of reproductive age.

  • Approximately 25% of women of reproductive age have symptoms related to UL. These symptoms include menorrhagia, pelvic pressure, infertility, and a range of complications during pregnancy.

  • UL are hormonally dependent tumors and are not observed prior to puberty. Estrogen, progesterone, and other small growth factors promote tumor growth. UL may regress at menopause.

  • Rarely, estimated at 0.1%, UL may progress to their malignant counterpart, uterine leiomyosarcoma (LMS).

• Differential diagnosis:

  • Adenomyosis, solid adnexal mass, focal myometrial contraction, and LMS

• Monogenic forms:

  • Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a disorder that predisposes the carrier to renal cell cancer and UL. HLRCC is caused by mutations in the FH gene encoding fumarate hydratase, an enzyme involved in the citric acid cycle.

• Family history:

  • There is evidence of genetic liability for UL. First-degree relatives of an affected individual are 2.2 times more likely to also have UL.

• Twin studies:

  • Monozygotic (MZ) twins have about twice the rate of hospitalization due to UL when compared to dizygotic (DZ) twins, and the correlation for hysterectomy in MZ twins is about twice that observed in DZ twins.

• Environmental factors:

  • Early-life exposure to diethylstilbestrol (DES), a synthetic estrogen, has been associated with the development of UL. Other conditions that affect estrogen levels in the body, including parity and obesity, are also linked to UL growth.

• Genome-wide associations:

  • A genome-wide linkage analysis for nonsyndromic UL has identified multiple linkage peaks with significant LOD scores. Fine mapping in two replication populations detected several markers in 17q25.3 associated with UL diagnosis. The associated markers are in linkage disequilibrium with each other including the genes FASN, CCDC57 and SLC16A3. Functional studies are required to elucidate the possible role of these genomic regions in UL predisposition.

• Pharmacogenomics:

  • Pharmacogenomics do not yet play a role in UL management.

Diagnostic Criteria and Clinical Characteristics

Diagnostic Criteria for UL

Diagnostic evaluation should include

• UL may be detected during a routine pelvic examination as a pelvic mass or enlarged uterus.

• Imaging studies, such as ultrasonography, magnetic resonance imaging (MRI), and computed tomography (CT) may be indicated to confirm the diagnosis.

• Family medical history is warranted to distinguish between nonsyndromic UL and HLRCC.

Clinical Characteristics

The most common symptoms of UL are abnormal uterine bleeding and pelvic pressure. Many women with UL present with varying degrees of menorrhagia, or heavy menstrual bleeding. If the tumors are exerting pressure on nearby organs, such as the bowel or bladder, women may also have problems with bowel movements and urinary frequency. Reproductive issues include recurrent miscarriage and infertility. Complications during pregnancy include premature labor, pain, bleeding, fetal ...