What is adenomyosis?

Adenomyosis: Definition, Diagnosis, and Management

Adenomyosis is a benign uterine disorder characterized by the presence of endometrial glands and stroma abnormally located within the myometrium (uterine muscle layer), causing uterine enlargement, heavy menstrual bleeding, dysmenorrhea, and potential fertility issues. 1

Pathophysiology

Adenomyosis likely develops through several mechanisms:

• Invagination theory: The most supported theory suggests that adenomyosis results from invasion of the basalis endometrium into the myometrium, causing alterations in the junctional zone 1, 2
• Embryologic theory: Some evidence suggests adenomyosis may result from misplaced pluripotent müllerian remnants 1
• Contributing factors: Sex hormone abnormalities, inflammation, fibrosis, and neuroangiogenesis play important roles in disease development 3, 2

The pathological process involves:

• Endometrial epithelial cells and stromal fibroblasts abnormally present in the myometrium
• Hyperplasia and hypertrophy of surrounding smooth muscle cells 2
• Non-cyclic, anti-apoptotic activity of the basalis endometrium associated with relative hyper-estrogenic states 4

Clinical Presentation

Adenomyosis typically presents with:

• Heavy menstrual bleeding (menorrhagia)
• Dysmenorrhea (painful menstruation)
• Dyspareunia (painful intercourse)
• Pelvic pain
• Infertility
• Enlarged, tender uterus on examination

However, it's important to note that some women may be asymptomatic 1, 3

Diagnosis

Adenomyosis was traditionally diagnosed only after hysterectomy, but modern imaging techniques now allow for non-invasive diagnosis 1, 3:

Imaging Findings

1. Transvaginal Ultrasound (TVUS):

   • 2D TVUS shows reasonable sensitivity and specificity
   • 3D TVUS is superior for diagnosis, especially for early-stage disease 1, 3
   • Can differentiate adenomyosis from uterine fibroids with high accuracy (sensitivity 96%, specificity 93%) 5

2. Magnetic Resonance Imaging (MRI):

   • Excellent for differentiating adenomyosis from fibroids and other conditions
   • Can identify both diffuse and focal forms of adenomyosis 5, 3

Diagnostic Criteria

Diagnosis is based on an integrated approach considering:

• Clinical symptoms
• Risk factors (typically multiparous women aged 40-50 years)
• Physical examination
• Imaging findings 3

Treatment Options

Treatment depends on symptom severity, patient age, and fertility desires:

Medical Management

• First-line therapy: Hormonal treatments including:
  • Progestin-containing IUDs
  • Combined oral contraceptives
  • GnRH agonists/antagonists
  • Selective progesterone receptor modulators (SPRMs)
• Non-hormonal options: NSAIDs and tranexamic acid for bleeding control 6

Minimally Invasive Procedures

• Uterine Artery Embolization (UAE)
• MR-guided Focused Ultrasound (MRgFUS)
• Radiofrequency ablation (RFA)
• Hysteroscopic procedures 6

Surgical Options

• Conservative surgery: Cytoreductive surgery (adenomyomectomy) for women desiring fertility preservation 6
• Definitive treatment: Hysterectomy remains the only definitive treatment for adenomyosis 1, 6, 4

Clinical Considerations

• Adenomyosis often coexists with other gynecologic conditions such as endometriosis and uterine fibroids, complicating diagnosis and treatment 1
• MRI can effectively differentiate adenomyosis from fibroids and other conditions that cause similar symptoms 5
• Doppler ultrasound shows specific patterns that help differentiate adenomyosis from fibroids (resistive index <0.7 and pulsatility index <1.2) 5

Prognosis

• Medical treatments provide temporary symptom relief but are not curative
• Conservative surgical approaches can improve symptoms and preserve fertility but carry risks of complications
• Hysterectomy provides definitive treatment with excellent long-term outcomes 6, 4

For patients with adenomyosis who desire future fertility, a careful approach balancing symptom management and fertility preservation is essential, as conservative treatments may have limitations in effectiveness.