, Volume 9, Issue 3, pp 294–297

Endometriosis of the round ligament: description of a clinical case and review of the literature

  • S. Licheri
  • G. Pisano
  • E. Erdas
  • S. Ledda
  • B. Casu
  • M. V. Cherchi
  • M. Pomata
  • G. M. Daniele
Case Report

DOI: 10.1007/s10029-004-0314-6

Cite this article as:
Licheri, S., Pisano, G., Erdas, E. et al. Hernia (2005) 9: 294. doi:10.1007/s10029-004-0314-6


We report a case of endometriosis of the round ligament in a 29-year-old woman, who complained of a lump with a diameter of about 2.5 cm in the right inguinal region, which increased in bulk and was accompanied by intense pain during the menstrual period. The clinical suspicion of inguinal endometriosis, supported by ultrasonography and Magnetic Resonance (MR), was confirmed by histological examination of the surgical specimen, which included the mass and the extraperitoneal segment of the round ligament.

The authors conclude that the appearance of a lump in the inguinal region associated with subjective and objective changes of the lesion in relation to the menstrual cycle must raise the suspicion of endometriosis among the possible diagnoses.


Endometrioma of the round ligament Endometriosis Inguinal lump 


Endometriosis is a common gynaecological pathology that accounts for 8–15% of women of fertile age on average in the fourth decade of life [1, 2, 3]. It is characterised by the development of ectopic endometrial tissue, which under the stimulus of ovarian hormones takes on the typical proliferative and functional aspects of a normal endometrium.

It only occasionally represents a disease of specific interest to the general surgeon, on account of its extra pelvic localisations, especially the skin (umbilical scar, surgical scars), the viscera (small intestine, left colon, rectum, appendix), and the groin [2, 3, 4, 5, 6, 7, 8, 9, 10, 11]. In the latter case it can be confused with other common affections of the inguinal-crural region, such as primitive or metastatic lymphadenopathies, soft tissue tumours, and foreign body granulomas. It rarely causes a clinical picture suggestive of irreducible or strangulated hernia such as to require urgent surgery [9, 12, 13, 14].

With this work the authors wish to contribute to clarifying the diagnostic problems relating to inguinal endometriosis, by presenting a well-documented case and by analysing the most significant data that have emerged from the literature.

Case report

The patient was a 29-year-old, nulliparous woman, menarche at 14 years of age, who had been on hormonal therapy for secondary dysmenorrhoea since the age of 24 years.

She had reported the presence, for a year, of a roughly roundish lump in the inguinal region, of a diameter of about 2.5 cm, covered by intact skin and associated with a piercing type of pain. In concomitance with the menstrual period, the lump increased moderately in size and the pain symptoms intensified, becoming tensive while lasting the entire menstrual flow and limiting her normal activities.

At the physical examination, the lump, which was proximal to the internal inguinal orifice, presented a finely granulous surface, faded boundaries, and fibrous consistency. It was mobile on the surface plane but fixed in depth, tender, and irreducible. It did not transmit any impulse to coughing.

With the clinical suspicion of “inguinal endometriosis”, the patient was submitted to ultrasonography and magnetic resonance (MR) of the right inguinal region, the latter for purely iconographic-didactic purposes.

Ultrasound examination of the surface tissues showed a 23×20.7×13 mm egg-shaped nodule in the right inguinal region, extending longitudinally along the axis of the inguinal canal. The mass had an inhomogeneous hypoechoic ultrasound structure and poorly defined boundaries, in which a small 6×4 mm anechoic area without spontaneous flow could be distinguished (Fig. 1).
Fig. 1

Ultrasonographic appearance: hypoechoic nodule with ill-defined edges and central anechoic area

In the right inguinal region, anterior to the femoral vessels, MR showed a 25×30 mm sized nodular mass limited by an irregular capsule, adhesive to the superficial musculofascial planes by means of peripheral spicules in which minute nodulations of a haematic content were distinguished. The middle part was occupied by a hyperintense area referable to a blood component (methemoglobin) (Fig. 2).
Fig. 2a–b

MR: Axial section SE T1 (a) and TSE T2 (b). Nodular swelling of almost 30 mm, surrounded by an irregular capsule, hyperintense in T1 and T2 because of haematic content secondary to endometriosis

To complete the diagnosis, and with the aim of excluding further localisations in the pelvis, a transvaginal ultrasonography was also carried out, suggestive of a small implant in the right vaginal fornix.

The patient was therefore submitted to surgery under spinal anaesthesia with a preoperative diagnosis of endometriosis of the round ligament.

At operation, a 3 cm sized lump was detected under the aponeurosis of the large oblique muscle, very close to the deep inguinal orifice; it was firmly adhesive to the extraperitoneal portion of the round ligament, to the internal oblique muscle, and to the transversalis fascia (Fig. 3). We thus proceeded to remove the lump en bloc with the inguinal segment of the round ligament, for a length of 4 cm. (Fig. 4). No hernial sac was detected. The posterior abdominal wall appeared solid as did the transversalis fascia: only the internal orifice was therefore sutured.
Fig. 3

The mass is freed from the adhesions with the internal oblique muscle and the transversalis fascia at the deep inguinal orifice

Fig. 4

The surgical specimen includes the nodule of endometriosis and the inguinal segment of the round ligament

On macroscopic examination, the surgical specimen presented an ovoid shape, a grey-brown colour, a fibrous consistency, and when cut it showed the presence of a viscous dark red liquid.

The histological examination confirmed the clinical diagnosis of “endometriosis of the round ligament” (Fig. 5).
Fig. 5

Histological examination: jalinous stroma with endometrial glands and some areas of previous hemorrhage

The postoperative course was regular and the patient was discharged two hours after the operation. She is under gynaecological observation regarding the vaginal localisation of endometriosis. Thirty months after surgery the patient presented no signs nor symptoms of a relapse.


Endometriosis of the extraperitoneal portion of the round ligament, or more generally of the inguinal region, was first described by Cullen in 1896, and represents a rare affection that accounts for 0.3–0.6% of patients affected by endometriosis [9, 15].

After reviewing the literature, it was possible to add another seven cases (including the one described by us) to the 61 reported by Proposito et al. in 2002 [2, 16, 17, 18, 19]. It is interesting to note that more than half of these cases (62%) date back to the last twenty years, and that this data shows that inguinal endometriosis is a pathology that has been previously underestimated. It is likely that in the future it may be diagnosed preoperatively with greater frequency than reported in the past, namely by Sataloff et al. in 1989 (in 38% of the cases) [14].

The mean age of the patients at diagnosis is 37 years (range: 22–67). The disease appears with the onset of a lump of diameter ~2–3 cm in the inguinal region, associated with increased bulk and more painful symptoms during the menstrual period in 50% of the cases [10, 15]. The right side is far more involved (94% of the cases), while bilateral involvement is exceptional (only one case described) [5].

In 37% of the patients, endometriosis of the round ligament is associated with a groin hernia (23 inguinal hernias and two crural hernias) [3].

Though rare, malignant degeneration is possible, as testified by the two cases recently described of adenocarcinoma [19, 20].

Among the diagnostic tools, colour Doppler ultrasound is the examination of choice. The peculiar characteristics of the ultrasound semeiotics are the nodular aspect of the lesion, its hypoechoic structure, and absence of perilesional or intralesional vascular flow [21]. This picture, which is also present in our observation, contributed to confirming the clinical suspicion.

Computed tomography (CT) proved useful for ruling out most of the pathologies of the inguinal region, but it is often unable to distinguish a nest of endometriosis from a haematoma [16, 22, 23]; such distinction resulted in the present case from MR, which could detect the small deposits of hemosiderin and methemoglobin typical of endometriosis [23].

According to personal experience and to the cases reported in the literature, diagnostic indications to CT and MR should be limited to the few cases where other diseases (in other words, malignant) are to be excluded. To do this, as shown in the works of Pérez-Seoane et al. and of Griffin and Betsill [24, 25], Fine Needle Aspiration may prove determinant; obviously a subsequent histological examination of the specimen is mandatory.

Surgery is based upon radical excision of the lesion en bloc with the extraperitoneal portion of the round ligament. Care should be taken not to weaken the posterior abdominal wall.

After surgery, a careful gynaecological assessment is recommended, considering that further intraperitoneal localisations may be associated in 91% of the cases [2].


Endometriosis is essentially a gynaecological disease; nevertheless, on account of its rare localisations (umbilicus, inguinal canal, colon-rectum, appendix, small intestine), it may also involve the general surgeon.

Endometriosis of the round ligament must always be suspected in the presence of an inguinal-crural lump associated with pain and increased bulk during the menstrual period; however, in silent or paucisymptomatic forms it must always be considered among the possible differential diagnoses, especially if the patient is at reproductive age.

Radical surgical excision represents the treatment of choice, since it allows a precise histological diagnosis and reduces the risk of relapse.

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • S. Licheri
    • 1
  • G. Pisano
    • 1
  • E. Erdas
    • 1
  • S. Ledda
    • 1
  • B. Casu
    • 1
  • M. V. Cherchi
    • 2
  • M. Pomata
    • 1
  • G. M. Daniele
    • 1
  1. 1.General Surgery II, Department of Surgical Sciences and Organ TransplantsUniversity of CagliariCagliariItaly
  2. 2.Institute of RadiologyUniversity of CagliariCagliariItaly

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