Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Pathophysiology | Clinical features | Diagnosis | Case reports | Treatment | Clinical images | Gross description | Gross images | Microscopic (histologic) description | Positive stains | Molecular / cytogenetics description | Differential diagnosis | Additional referencesCite this page: Balakrishna J, Sharabi A. Endometriosis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lymphnodesendometriosis.html. Accessed April 10th, 2021.
Definition / general
- Endometriosis: the presence of endometrial glands and stroma in extrauterine sites
- Lymph node involvement by endometriosis is uncommon and consists of isolated endometriotic-like cells located in the peripheral sinus of lymph node and frank metastatic endometriotic lesions
Terminology
- Lymphatic endometriosis
- Metastases from endometriosis
Epidemiology
- Endometriosis is a common disease affecting up to 15% of women of reproductive age
- In women with ovarian or peritoneal endometriosis, endometriotic lesions are found in 11% and isolated endometriotic-like cells in 80% of pelvic sentinel lymph nodes
- Spread of endometriosis is common in women with rectosigmoid, rectovaginal, and bowel endometriosis
Sites
- Regional lymph nodes including mesorectal, pericolic and pelvic lymph nodes
Pathophysiology
- May result from vascular drainage; in rectosigmoid endometriosis, by lymphovascular invasion by glands or stroma
- Lymph node involvement represents a metaplastic process from the conceptual secondary Müllerian system
- A process similar to malignant transformation allows some endometriotic cells from the primary endometriotic lesion (EL) to detach and to colonize regional pelvic sentinel lymph nodes (PSLN)
Clinical features
- Pelvic pain, infertility, dysmenorrhea
- May cause infertility
- Malignant transformation can occur rarely
Diagnosis
- Lapraoscopy
- Biopsy
Case reports
- 40 year old woman with abdominal pain (University of Pittsburgh Case #375)
- Endometriosis of the bowel with lymph node involvement (Pathol Res Pract 1996;192:957)
Treatment
- Similar to primary endometriosis
- Lymph node dissection may be helpful
Clinical images
Gross description
- Enlarged lymph nodes
- May or may not show hemorrhagic cut surfaces
Microscopic (histologic) description
- Glandular cystic spaces lined by Müllerian serous epithelium and endometrioid stroma
- Recent and old hemorrhage and fibrosis may be seen
- May undergo decidual reaction
- Variable hemorrhage
- Rarely has smooth muscle component
Positive stains
Molecular / cytogenetics description
- May show upregulation of chemokine receptor CXCR4 and CD44 isoforms, and loss of expression of epithelial markers such as E-cadherin and EPCAM (Eur J Obstet Gynecol Reprod Biol 2013;169:370)
Differential diagnosis
- Metastasis from endometrial adenocarcinoma
- Other Müllerian abnormalities unaccompanied by stroma including:
- Benign Müllerian cysts: Müllerian glands lined by nonciliated epithelium
- Endosalpingiosis: Müllerian glands lined by ciliated tubal epithelium
Additional references