Can Endometriosis Involve the Esophagus?
Yes, endometriosis can theoretically occur in the esophagus, but this is extraordinarily rare and not documented in standard endometriosis guidelines or classification systems.
Understanding Endometriosis Location
Endometriosis is defined as endometrial-like tissue located outside the endometrial cavity, typically occurring in predictable pelvic locations 1. The disease usually manifests as:
- Pelvic endometriosis (most common)
- Deep endometriosis extending below the peritoneum
- Gastrointestinal involvement when it occurs outside typical pelvic sites
Gastrointestinal Tract Involvement Pattern
When endometriosis affects the GI tract, it follows a specific anatomic distribution 2:
- Appendix (most frequent GI site - 77 cases in institutional cohort)
- Rectum (45 cases)
- Sigmoid colon (40 cases)
- Other intestinal segments (rare)
Notably, esophageal involvement is not mentioned in any of the reviewed guidelines or recent large institutional series of GI endometriosis 2. The 2024 ACR guidelines specifically note that endometriosis "typically occurs in predictable locations in the pelvis" and when discussing expanded imaging protocols, they evaluate structures like the uterosacral ligaments, rectosigmoid wall, appendix, and diaphragm—but not the esophagus 1.
Clinical Reality
In a comprehensive institutional cohort of 1,964 endometriosis cases, only 150 (7.7%) demonstrated GI tract involvement, and none involved the esophagus 2. The anatomic distribution strongly favors pelvic and lower GI structures, likely due to:
- Proximity to the uterus and peritoneal cavity
- Retrograde menstruation theory (most accepted pathogenesis)
- Direct extension or lymphatic/vascular spread from pelvic disease
Important Caveat
While an association between GERD and endometriosis has been studied 3, this represents a potential causal relationship between the two conditions rather than esophageal endometriosis itself. The research suggests GERD may increase risk of uterine-confined endometriosis, not that endometriosis implants in the esophagus.
Clinical Approach
If a patient presents with esophageal symptoms and known endometriosis:
- Do not assume esophageal endometriosis as the cause
- Pursue standard evaluation for esophageal pathology
- Consider that GERD and endometriosis may coexist as separate entities 3
- Extremely rare case reports may exist in literature, but this would be a diagnosis of exclusion requiring histologic confirmation
In practical terms, esophageal endometriosis is so rare that it should not be on the differential diagnosis unless all other causes have been excluded and histologic confirmation is obtained.