Inguinal Endometriosis – A Series of Five Cases and Literature Review

Abstract

Case report he found IE in 0.6% of the patients (3). Sun et al, in a retrospective study between 1986-2008, found an incidence of 0.07% (9 in 13,352 patients) (4). IE generally involves the extraperitoneal portion of the round ligament, but it may be found in inguinal lymph nodes, subcutaneous adipose tissue or in the wall of sacs of inguinal or femoral hernias (5). Due to its rarity, the correct diagnosis of IE poses a challenge as it can mimic the whole range of inguinal pathology and be often misdiagnosed as inguinal hernia, lymphadenopathy, abscess, lymphoma, lipoma, hematoma or subcutaneous cyst (1, 2, 5). Therefore, the real prevalence of IE is probably underreported. IE pathogenesis is not yet completely understood. There are several possible theories: 1) implantation of endometrial tissue by transtubal regurgitation during the menstrual cycle; 2) via hematological or lymphatic spread of endometrial cells; 3) congenital hormonal activation of embryonal cells from the Müllerian duct; 4) metaplasia of mesothelial cells and direct extension from the pelvis along the round ligament (1). The reason why the right side is much more affected remains unclear, but it can be due to: asymmetrical lymphatic drainage in favor of the right inguinal and femoral region; protection of the left inguinal canal by the sigmoid colon; endometrial cells remaining on the right side for a longer period due to clockwise flow of intraperitoneal fluid (2, 4, 6).

Noninvasive Duplex Ultrasound Findings of Left-Sided Inguinal Endometriomas

“…9 Partly because the incidence is so rare, diagnosis is often made in a very delayed fashion and on surgical exploration, either for symptoms, or to exclude malignancy or inguinal hernia. [8][9][10][11][12][13] Computed tomography, magnetic resonance imaging, and ultrasonography have all been used to evaluate suspected inguinal lesions. There is debate among the various authors how accurate these diagnostic strategies are, with some finding them not helpful, and others expressing a great deal of confidence in them.…”

“…5,6 Although rare, inguinal endometriosis should be considered as a potential diagnosis when scanning patients of childbearing age with complaints of inguinal pain. [10][11][12][13][14][15] In this clinical setting, focused inguinal duplex can provide the diagnosis, obviating the need for surgical or other forms of invasive biopsy. In addition, the response to treatment can be followed noninvasively.…”