Ovarian cyst

Introduction
An ovarian cyst is a fluid-filled sac within or on the surface of an ovary. These cysts are common in women of reproductive age, often asymptomatic, and usually benign. They can be functional (related to ovulation) or pathological (arising from benign or malignant tumors). While many resolve spontaneously, some may cause symptoms or complications requiring medical or surgical intervention.

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Classification

1. Functional (Physiological) Cysts

• Follicular cysts: Result from a dominant follicle failing to rupture; usually <5–8 cm, resolve within 1–3 cycles.

• Corpus luteum cysts: Develop after ovulation when the corpus luteum seals and fills with fluid or blood; may cause delayed menstruation or pain.

• Theca lutein cysts: Associated with high hCG states (multiple gestation, molar pregnancy, ovarian hyperstimulation).

2. Pathological Cysts

• Benign neoplasms:

  • Serous cystadenoma.

  • Mucinous cystadenoma.

  • Mature cystic teratoma (dermoid cyst).

• Endometriotic cysts (endometriomas): “Chocolate cysts” containing altered blood.

• Malignant tumors: Epithelial ovarian cancer, germ cell tumors, stromal tumors.

3. Other

• Paraovarian cysts: Arise from broad ligament; not part of the ovary itself.

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Epidemiology

• Common in women of reproductive age due to ovulatory cycles.

• Incidental detection has increased with widespread use of pelvic imaging.

• Functional cysts rare after menopause; any postmenopausal cyst should be evaluated for malignancy risk.

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Risk Factors

• Reproductive age.

• Ovulatory cycles (increased gonadotropin stimulation).

• Hormonal imbalances.

• Endometriosis (for endometriomas).

• Pregnancy (for corpus luteum cysts).

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Clinical Features

Asymptomatic: Many cysts are incidental findings.

Symptomatic:

• Lower abdominal or pelvic pain (intermittent, dull, or sharp).

• Menstrual irregularities.

• Dyspareunia (pain during intercourse).

• Bloating or fullness in abdomen.

Acute presentation:

• Ovarian torsion: Sudden severe unilateral pelvic pain, nausea, vomiting.

• Cyst rupture: Acute pain, sometimes with internal bleeding and peritoneal signs.

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Complications

• Ovarian torsion.

• Cyst rupture with hemoperitoneum.

• Hemorrhage into cyst.

• Infection.

• Malignant transformation (rare in benign cysts).

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Diagnosis

1. Clinical assessment

• History: Pain onset, menstrual history, reproductive history.

• Examination: Pelvic or abdominal mass, tenderness.

2. Imaging

• Transvaginal ultrasound (TVUS): First-line imaging; assesses size, morphology, wall thickness, septations, papillary projections, and solid components.

• Color Doppler: Evaluates vascularity (high flow in malignancy, absent flow in torsion).

3. Laboratory tests

• Pregnancy test (β-hCG) in reproductive-age women to exclude ectopic pregnancy.

• Tumor markers (when malignancy suspected):

  • CA-125 (nonspecific; elevated in epithelial ovarian cancer, endometriosis, PID).

  • AFP, β-hCG, LDH for germ cell tumors (younger women).

• Complete blood count (CBC) if rupture/bleeding suspected.

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Management

1. Observation (Expectant Management)

• For simple, unilocular cysts <5–7 cm in reproductive-age women:

  • Repeat TVUS in 6–12 weeks to ensure resolution (most functional cysts resolve spontaneously).

2. Medical Therapy

• Combined oral contraceptives (COCs): Prevent formation of new functional cysts by suppressing ovulation (not useful for shrinking existing cysts).

• Analgesia: NSAIDs for pain relief.

3. Surgical Management

• Indications:

  • Persistent cysts >5–10 cm.

  • Symptomatic or complicated cysts (torsion, rupture, hemorrhage).

  • Suspicious ultrasound features (solid areas, papillary projections, high vascularity).

  • Postmenopausal cysts (especially >5 cm or complex).

• Procedures:

  • Cystectomy: Excision of cyst with preservation of ovary.

  • Oophorectomy: Removal of entire ovary (if malignancy suspected or extensive damage).

  • Minimally invasive (laparoscopy) preferred unless malignancy suspected (laparotomy).

4. Malignancy Management

• Referral to gynecologic oncologist for suspected malignant cysts.

• Staging laparotomy if indicated.

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Prevention and Follow-up

• Functional cysts cannot be entirely prevented except by ovulation suppression (COCs).

• Regular follow-up imaging for complex or persistent cysts.

• Early evaluation in postmenopausal women to rule out malignancy.

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Prognosis

• Most functional cysts resolve spontaneously.

• Pathological cyst outcomes depend on histology; early detection of malignant cysts improves survival.

• Risk of recurrence exists, especially with dermoid cysts and endometriomas.