What are the diagnosis and treatment options for endometriosis?

Diagnosis and Treatment of Endometriosis

Diagnosis

Endometriosis is fundamentally a clinical diagnosis that does not require surgical confirmation before initiating treatment, with transvaginal ultrasound (TVUS) as the initial imaging modality and expanded protocol TVUS or MRI pelvis for detecting deep disease. 1

Clinical Diagnostic Criteria

The diagnosis begins with identifying characteristic symptom patterns:

• Pain patterns include dysmenorrhea, dyspareunia (painful intercourse), dyschezia (painful defecation), dysuria (painful urination), or chronic pelvic pain 1
• Infertility is present in approximately 50% of patients with endometriosis 1, 2
• Physical examination findings may reveal nodularity, fixed retroverted uterus, or tender uterosacral ligaments, though normal examination does not exclude the diagnosis 1, 2

Imaging Algorithm

First-line imaging:

• Standard TVUS is the initial imaging modality recommended by the American College of Radiology 3, 1
• Expanded protocol TVUS (requiring specialized training) includes evaluation of uterosacral ligaments, anterior rectosigmoid wall assessment, dynamic sliding maneuvers, and evaluation of appendix and diaphragm—this demonstrates excellent performance for deep endometriosis detection comparable to MRI 3, 1

Second-line imaging:

• MRI pelvis without IV contrast is the next step if TVUS is inconclusive or for surgical planning, showing 90.3% sensitivity and 91% specificity for deep pelvic endometriosis 1
• MRI with IV contrast is highly recommended to differentiate endometriomas from ovarian malignancies 1
• Transabdominal ultrasound can be added to widen the field of view for urinary tract and bowel involvement beyond the pelvis 3, 1

Imaging to avoid:

• CT pelvis has no role in standard endometriosis diagnosis 3, 1

Laboratory Testing

• CA-125 has no clinical utility for diagnosis and should not be used for diagnostic purposes 1
• CA-125 may be helpful for monitoring clinical response in patients with confirmed extrauterine disease, but can be falsely elevated due to peritoneal inflammation or infection 1

Surgical Diagnosis

• Laparoscopy with histologic confirmation is no longer required before initiating empiric treatment 1
• Surgery is now reserved for definitive treatment rather than diagnosis, as preoperative imaging reduces morbidity by decreasing incomplete surgeries requiring reoperation 1

Critical Diagnostic Pitfalls

• Do not rely on standard TVUS alone for deep endometriosis—expanded protocols or MRI are needed 1
• Do not assume negative imaging excludes endometriosis—superficial peritoneal disease is poorly detected by all imaging modalities 1
• Recognize diagnostic delay averages 5-12 years after symptom onset, with most women consulting 3 or more clinicians prior to diagnosis 2

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Treatment

Hormonal medications (combined oral contraceptives or progestins) are first-line treatment for symptomatic premenopausal women not currently desiring pregnancy, with surgical removal of lesions reserved for cases where hormonal therapies are ineffective or contraindicated. 2

First-Line Medical Treatment

Hormonal therapy options (all showing similar effectiveness):

• Combined oral contraceptives reduce pain by 13.15-17.6 points on a 0-100 visual analog scale compared to placebo 2
• Progestins (medroxyprogesterone acetate or megestrol acetate) reduce the size of endometriotic lesions and are considered first-line due to favorable safety profile, tolerability, and cost-effectiveness 4
• Continue hormonal therapy as long as symptoms persist and fertility is not immediately desired 4

Treatment limitations to counsel patients about:

• 11-19% of individuals have no pain reduction with hormonal medications 2
• 25-34% experience recurrent pelvic pain within 12 months of discontinuing hormonal treatment 2
• Approximately one-third of symptomatic women globally do not respond to progestins and low-dose oral contraceptives, likely due to progesterone resistance 5

Second-Line Medical Treatment

GnRH agonists or antagonists should be considered if first-line therapies prove ineffective, are poorly tolerated, or contraindicated:

• GnRH agonists for at least 3 months with add-back therapy to reduce or eliminate GnRH-induced bone mineral loss without reducing pain relief efficacy 4
• Oral GnRH antagonists constitute an effective and tolerable therapeutic alternative with fewer side effects than other therapies 5
• Danazol for at least 6 months is equally effective to GnRH agonists for pain relief in most women 4

Third-Line Medical Treatment

• Aromatase inhibitors are third-line treatment options 2

Surgical Treatment

Indications for surgery:

• First-line hormonal therapies are ineffective or contraindicated 2
• Severe endometriosis where medical treatment alone is insufficient 4

Surgical approach:

• Laparoscopic removal of lesions is the standard surgical approach 2
• Surgery is associated with significant reduction in pain during the first 6 months following the procedure 4

Surgical outcomes to counsel patients about:

• Up to 44% of women experience symptom recurrence within one year after surgery 1, 4
• For rectosigmoid bowel lesions, surgical options include shaving, discoid resection, or segmental resection based on preoperative imaging 3

Definitive Surgical Treatment

• Hysterectomy with surgical removal of lesions may be considered when initial treatments are ineffective 2
• Approximately 25% of patients who undergo hysterectomy for endometriosis experience recurrent pelvic pain 2
• 10% undergo additional surgery (such as lysis of adhesions) to treat pain 2

Surgical Classification Systems

For women undergoing surgery, the World Endometriosis Society recommends completing:

• r-ASRM classification for all women 3
• Enzian classification additionally for women with deep endometriosis 3
• Endometriosis Fertility Index (EFI) additionally for women for whom future fertility is a concern 3

Monitoring and Follow-up

• Clinical evaluation every 6 months is recommended to assess treatment response and potential side effects 4
• For ovarian endometriomas, careful imaging follow-up with transvaginal ultrasound to monitor size changes 4

Special Considerations

• Expectant management may be appropriate if the patient becomes asymptomatic, as endometriosis is often unpredictable and may regress 4
• Women with endometriosis have increased cardiovascular risk, including stroke (HR 1.34,95% CI 1.10-1.62) 1
• Endometriosis is associated with recurrent pregnancy loss and infertility, which may warrant pre-conception treatment 1