Gynecology Topic 32. Endometriosis and adenomyosis

I. Endometriosis

Definition

• Endometriosis: Presence of endometrial-like glands and stroma outside the uterine cavity and myometrium.
• Estrogen-dependent chronic inflammatory disease of reproductive age.
• Important associations: Chronic pelvic pain and infertility.

Common Sites

• Ovaries → Endometrioma/chocolate cyst containing thick, brown, old blood.
• Pelvic peritoneum, anterior/posterior cul-de-sac (Douglas pouch).
• Uterosacral ligaments, posterior fornix/rectovaginal septum.
• Urinary bladder, ureter, colon/rectosigmoid.
• Rare distant disease can occur through lymphatic/hematogenous spread.

Theories of Etiology

• Retrograde menstruation (Sampson theory): Menstrual blood containing endometrial tissue refluxes through the fallopian tubes → Implantation on peritoneal surfaces.
• Lymphatic/hematogenous spread → Explains distant lesions.
• Coelomic metaplasia → Peritoneal mesothelium transforms into endometrial-like tissue.
• Genetic/immune factors may influence implantation and persistence.

Pathology

• Implants respond to cyclic estrogen/progesterone changes → Bleeding, inflammation, fibrosis and adhesions.
• Classic peritoneal lesions: Brown-black "powder-burn/gunshot" lesions.
• Advanced disease → Adhesions, fixed organs, frozen pelvis.

II. Endometriosis: Clinical Features

Symptoms

• Classic triad: Dysmenorrhea + deep dyspareunia + dyschezia.
• Cyclic pelvic/lower abdominal pain → Begins before menses and peaks around menstruation.
• Progression: Cyclic pain → Chronic continuous pelvic/abdominal pain with menstrual exacerbation.
• Dyspareunia, dyschezia/painful defecation, dysuria.
• Infertility/subfertility → Adhesions, distorted anatomy, inflammatory pelvic environment.
• Pain severity does not reliably correlate with visible disease extent.

Physical Examination

• May be normal.
• Retroverted, fixed uterus.
• Uterosacral ligament tenderness or nodules.
• Tender nodules in the posterior vaginal fornix/rectovaginal septum.
• Tender, fixed adnexal mass → Ovarian endometrioma.

III. Endometriosis: Diagnosis

Work-Up

• Clinical suspicion based on cyclic pelvic pain, dysmenorrhea, dyspareunia, dyschezia and infertility.
• Exclude pregnancy, PID/STI, UTI, ovarian cyst/torsion and GI disease when symptoms suggest them.

Imaging

• Transvaginal US → 1st-line for ovarian endometrioma and pelvic mass.
• Endometrioma on US: Homogeneous low-level internal echoes / "ground-glass" appearance.
• MRI → Deep infiltrating disease, bowel/bladder/ureter involvement, preoperative mapping.
• Negative imaging does not exclude superficial peritoneal endometriosis.

Laparoscopy and Histology

• Laparoscopy ± biopsy remains definitive/gold-standard confirmation when diagnosis is uncertain, symptoms persist, infertility surgery is planned, or deep/severe disease is suspected.
• Findings: Gunshot/powder-burn lesions, adhesions, endometriomas/chocolate cysts.
• Histology: Endometrial glands and stroma ± hemosiderin-laden macrophages.
• Empiric hormonal treatment can be started without laparoscopy when symptoms are typical and no red flags are present.

IV. Endometriosis: Treatment

Principles

• Treatment depends on pain severity, lesion type/location, infertility desire, age, contraindications and recurrence.
• Goals: Pain control, hormonal suppression, fertility preservation/treatment, recurrence prevention.

Medical Treatment

• NSAIDs → Pain relief, especially mild/moderate dysmenorrhea.
• Hormonal suppression:

• Combined OCPs, cyclic or continuous.
• Progestins / levonorgestrel-IUD.
• GnRH agonist, e.g. leuprolide → Pseudomenopause; add-back therapy if prolonged use.

• Medical suppression improves pain but does not remove adhesions or restore distorted anatomy.

Surgical Treatment

• Conservative surgery: Laparoscopic excision or ablation of visible implants + adhesiolysis + endometrioma cystectomy when indicated.
• Indications: Persistent pain despite medical therapy, endometrioma, infertility with distorted anatomy, bowel/bladder/ureter involvement, diagnostic uncertainty.
• Definitive surgery: TAH-BSO ± excision of residual implants → Severe recurrent disease in patients who completed childbearing.
• Postoperative hormonal suppression may reduce pain recurrence if pregnancy is not desired immediately.

V. Adenomyosis

Definition and Epidemiology

• Adenomyosis: Presence of endometrial glands and stroma within the myometrium.
• Common in parous women aged 30-50 years.
• May be diffuse or focal; often associated with enlarged, tender uterus.

Pathology

• Endometrial basalis invades the myometrium → Myometrial hypertrophy/hyperplasia.
• Uterus becomes diffusely enlarged, globular and often tender.
• Histology: Endometrial glands and stroma within myometrium beneath the endometrial-myometrial junction.

VI. Adenomyosis: Clinical Features and Diagnosis

Clinical Features

• May be asymptomatic.
• Pelvic pain, dysmenorrhea → May become chronic continuous pelvic pain.
• Menorrhagia/heavy prolonged bleeding → Anemia.
• Dyspareunia, dyschezia or dysuria can occur, especially with enlarged uterus or coexisting endometriosis.
• Infertility/subfertility may occur.

Physical Examination

• Diffusely enlarged, globular, soft/boggy and tender uterus.
• May be asymmetric → Can mimic leiomyoma.

Diagnosis

• Transvaginal US → 1st-line.

• Diffusely enlarged uterus, thickened/heterogeneous myometrium, myometrial cysts, thickened junctional zone.

• MRI → Most accurate imaging, useful if US is inconclusive or to distinguish from fibroids.
• CBC → Anemia if heavy bleeding.
• Definitive diagnosis: Histology after hysterectomy.

VII. Adenomyosis: Treatment

Medical Treatment

• NSAIDs → Pain/dysmenorrhea.
• Combined OCPs or progestin-only therapy → Hormonal suppression.
• Levonorgestrel-IUD → Very effective for heavy bleeding and pain control.
• GnRH agonist (leuprolide) → Short-term symptom reduction, often preoperative or refractory cases.

Procedural/Surgical Treatment

• Definitive treatment: Hysterectomy.
• TAH-BSO is not routinely required for adenomyosis unless another indication exists; ovaries may be preserved depending on age/risk.