Ovarian cysts

Section: Emergency Curriculum: Curriculum, page 29

Definition

• Fluid filled sac arising from the ovary which can be simple or complex

Epidemiology

• Almost all premenopausal women and 20% of postmenopausal women
• <0.01% risk of malignancy - 15/100,000

Pathophysiology

• Functional cysts
  • Related to menstrual cycle
    • Follicular phase (1st half) - high FSH → priming of dominant follicle
    • E2 and LH surge → ovulation and dominant follicle release
    • Remnant → corpus luteum - makes P4
• Endometrioma
  • Blood filled cysts arising from ectopic endometrium

Classification → simple vs complex

• Functional
  • Follicular
  • Corpus luteal
  • Theca lutein
• Luteoma of pregnancy
• Neoplastic
• PCOS
• Endometrioma

Aetiology/Risk factors

• Infertility treatment
• Tamoxifen
• Pregnancy
• Hypothyroidism
• Smoking
• Tubal ligation

Clinical

• Asymptomatic to local and hormonal sx - lower abdominal pain, dyspareunia, altered bowel habit and cycle irregularity

Investigations

• Bloods - usual with hCG
• Urinalysis and pregnancy tests
• Swabs - R/O PID/STI
• Ca-125 if suspicion for ovarian cancer
• Imaging
  • USS - TV/TA
    • Simple - thin, round, hypo or anechoic, posterior acoustic shadow
    • Complex - septated, thick, projections in or out
    • Torsion of ovary - enlarged, oedema, flow reduced
  • CT - best to assess haemorrhage into cyst or abdomen

Work up of adnexal mass

• Hx/OE
• Bloods including Hb, Ca-125
• USS pelvis/TV/TA +/- CT
• Referral to gynae and gynae onc MDM?
• Differential Diagnosis
  • GUT
  • TOA, rupture ectopic, ovarian or cyst torsion, ruptured haemorrhagic cyst
  • GIT
  • Appendicitis and its differentials

Management

• Simple and small
• Larger and persistent - USS surveillance initially 3 monthly and get a normal Ca-125
  • Surgery
    • Indications
      • Persistent simple cysts >5cm
      • Symptomatic
      • Complex
    • Approach
      • Laparoscopic
      • Open - usually if malignant
      • Malignant - bilateral ooph§±erectomy
    • Simple
      • Consider cystectomy to retain ovary for hormonal purposes or if family is not complete
• Principles of management for cystic ovarian lesions
  • Define if issue is emergency or not
  • Define likelihood of benign vs malignant pathology
  • Define if cyst is symptomatic
  • Consideration of inducing menopause with surgery and fertility
    • Age of patient, family complete
    • Pre vs postmenopausal
  • Ongoing surveillance - USS
  • Patient wishes
• Rhesus isoimmunisation
  • If a mother has rhesus ABs (tested as part of usual pregnancy bloods)
  • Requirement for anti-RHD Ig to be given prior to birth
  • Develops when a Rh negative mother has an Rh positive baby
  • Maternal exposure to fetal blood
  • Mother develops IgM response
  • Cant cross the placenta as too large
  • On next exposure - mounts memory IgG response which can cross placenta
  • Causes HDN and fetal hydrops
  • Prevention by giving an rhesus mother Anti-D Ig during pregnancy

Prognosis

• Complications
  • Torsion - 15% of cysts >4cm
  • Rupture
  • Haemorrhage
• Natural history
  • Benign cysts majority are functional and will self resolve