Endometriosis affects up to 10% of women of reproductive age or, conservatively, about 6.5 million women in the United States.1,2 There are 3 types of endometriosis—superficial, ovarian, and deep—and in the past each of these was assumed to have a distinct pathogenesis.3 Deep infiltrating endometriosis (DIE) is the presence of one or more endometriotic nodules deeper than 5 mm. In a study at a large tertiary-care center, 40% of patients with endometriosis had deep disease.4 DIE is associated with more severe pain and infertility.5 In patients with endometriosis, diagnosis is commonly made 7 to 9 years after the initial pelvic pain presentation.6 For these reasons, well-directed history taking and proper evaluation and treatment should be pursued to relieve pain and optimize outcomes.
CASE Young woman with intensifying pelvic pain
Mary is a 26-year-old social worker who presents to her ObGyn with symptoms of worsening pain during as well as outside her periods. What additional information would you want to obtain from Mary, given her chief symptom of pain?
Investigate the type of pain
It is important to ask the patient about her menstrual and sexual history, her thoughts regarding near- and long-term fertility, and the type and severity of her pain symptoms. The 5 pain symptoms specific to pelvic pain are dysmenorrhea, dyspareunia, dysuria, dyschezia, and noncyclic pelvic pain. A visual analog scale (VAS) for pain as well as pelvic pain questionnaires can be used to guide evaluation options and monitor treatment outcomes. In addition, it is of paramount importance to understand the differential diagnoses that can present as pelvic pain (TABLE).
CASE Continued: Mary’s history
Mary reports that she always has had painful periods and that she was started on oral contraceptive pills for pain control and regulation of her periods soon after the onset of menses, when she was 12 years old. In college, she was prescribed oral contraceptive pills for contraception. Recently engaged, she is interested in becoming pregnant in 3 years.
A year ago, Mary discontinued the pills because of their adverse effects. Now she has severe pain during (VAS score, 8/10) and outside (VAS score, 7) her monthly periods. Because of this pain, she has taken time off from work twice within the past 6 months. She has pain during intercourse (VAS score, 7) and some pain with bowel movements during her menses (VAS score, 4). Pelvic examination reveals a normal-sized uterus and adnexa as well as a tender nodule in the rectovaginal septum.
What diagnostic tests and imaging would you obtain?
Imaging’s role in diagnosis
At many advanced centers for endometriosis, DIE is successfully diagnosed with specific magnetic resonance imaging (MRI) or transvaginal ultrasound (TVUS) protocols. In a recent review, MRI’s pooled sensitivity and specificity for rectosigmoid endometriosis were 92% and 96%, respectively.7 Choice of imaging for DIE depends on the skills and experience of the clinicians at each center. At a large referral center in São Paulo, Brazil, TVUS with bowel preparation had better sensitivity and specificity for deep retrocervical and rectosigmoid disease compared with MRI and digital pelvic examination.8 In addition, at a center in the United States, we found that proficiency in performing TVUS for DIE was achieved after 70 to 75 cases, and the exam took an average of only 20 minutes.9
Despite recent advances in imaging, most gynecologic societies still hold that endometriosis is to be definitively diagnosed with histologic confirmation from tissue biopsies during surgery. Although surgery remains the diagnostic gold standard, it does not mean that all patients with pelvic pain should undergo diagnostic laparoscopy with tissue biopsies.
The combination of compelling clinical signs, symptoms, and imaging findings (such as absence of findings for ovarian and deep endometriosis) can be used to make a presumptive nonsurgical (that is, clinical) diagnosis of endometriosis. Major societies recommend empiric medical therapy (for example, combination oral contraceptives) for the pain associated with superficial endometriosis.10,11 When there is no response to treatment, or when a patient declines or has contraindications to medical therapy, diagnostic laparoscopy with excision of endometriosis should be considered.
CASE Continued: Diagnosis
Mary undergoes TVUS with bowel preparation, which reveals a normal uterus and adnexa and the presence of 2 lesions, a 2×1.5-cm retrocervical lesion and a 1.8×2-cm rectosigmoid lesion 9 cm above the anal verge. The rectosigmoid lesion involves the external muscularis and compromises 30% of the bowel circumference.
How would you manage the bowel DIE?