Leiomyoma of round ligament masquerading as an inguinal hernia

Round ligament originates from the uterus extending through the inguinal canal and terminates at the mons pubis and labia majora and is mainly composed of smooth muscle fibers, connective tissue, vessels, and nerves with a mesothelial coating. Tumor of the round ligament of the uterus is rare, with leiomyoma being the most common followed by endometriosis and mesothelial cysts. Most of the leiomyomas in round ligament are presenting as inguinal masses in women of reproductive age group and the exact incidence is unknown. Abdomen and vulva are the other locations for such tumor.[] Leiomyoma of round ligament of uterus presenting as mass in the inguinal canal is usually confused with inguinal hernia.[] Extraperitoneal round ligament leiomyomas are uncommon tumors, with only a handful of case studies and case series published so far. Hence, we report this rare case for information and pertinent discussion. CASE REPORT A 47-year-old parous woman presented to us with complaints of heavy menstrual bleeding for 2 years, not controlled on medical management. She also had a complaint of a mass felt over the right groin area and not associated with pain. The mass increased in size on coughing or sneezing. She had no other associated complaints. She had no significant medical or past surgical history and no family history of any malignancies. On groin examination, a soft, nontender, fluctuant mass of size approximately 5 cm × 4 cm was found in the right inguinal region extending into the right labia majora and was reducible on cough impulse. A provisional diagnosis of inguinal hernia was arrived at. On speculum and bimanual pelvic examination, cervix was healthy, uterus bulky, and mobile with no adnexal masses. Digital rectal examination of the patient was normal. Preoperative ultrasound of pelvis done showed features of adenomyosis of uterus and an ill-defined inguinal mass with features of hernia. With the abovementioned findings, a provisional diagnosis of adenomyosis of uterus with inguinal hernia was made. Nondescent vaginal hysterectomy with inguinal hernia repair was planned. Following the hysterectomy, the right inguinal canal was explored and a well-circumscribed firm mass of size approximately 7 cm × 5 cm × 4 cm was found within a layer of white fibrous tissue. The mass was found to be originated from the inguinal insertion of round ligament [Figure 1a] and was excised in toto [Figure 1b]. The excised specimen was sent to the pathology department for histopathological examination. The round ligament mass on microscopic examination revealed features of leiomyoma [Figure 2a and b]. Endometrium showed secretory changes while myometrium showed adenomyotic changes and cervix had features of chronic cervicitis. The patient is without any recurrence of the disease after 5 months of the operation.

Leiomyomas are the benign neoplasm of smooth muscle origin and can theoretically arise in any tissue containing these elements. These are the most common benign neoplasms of female reproductive tract, with an estimated incidence of 20%–40% in reproductive years.[] The most common site of occurrence is intramural. Rarely, they have been documented to arise in the round ligament, liver, trachea, and even ciliary body of the orbit.[] Uterine leiomyoma is a common finding. However, leiomyoma of round ligament is rare and 50% of cases associated with uterine fibroids. Most of the cases are detected in women of the reproductive age, with individual cases diagnosed in the postmenopausal age group. Estrogen and progesterone receptors are usually positive.[] Tumor found in the inguinal canal can be both benign and malignant. Inguinal swellings most commonly are inguinal hernias although the other differential diagnoses include tumors, cysts, abscesses, adenopathy, preperitoneal lipoma, lymphadenitis, hematoma, neurofibroma, desmoid tumor, femoral artery aneurysm, uterine fibroids, endometriosis, saphena magna thrombophlebitis, metastases, dermoid, and hydrocele of the canal of Nuck.[,,] Around 50% of round ligament leiomyomas arise from the extraperitoneal site, particularly in the inguinal canal, clinically mimicking inguinal hernias. These tumors are more common on the right side, reason for which remains largely unknown.[] The etiopathology for these tumors to develop in these unlikely locations has been speculated to be somatic mutations of normal smooth muscle and a complex interaction between sex steroids and interplay of local growth hormones. Estrogen plays a major promoter for the myoma growth, whereas the role of progesterone is unclear.[] Computed tomography scans may help in the diagnosis of leiomyoma before surgical exploration, but is not usually employed and shows a circumscribed, heterogeneous, dense mass possible mottled, whorled, streaked, and curvilinear pattern of calcifications.[] Preoperative magnetic resonance imaging (MRI) is one of the best modalities to categorize the inguinal swellings in case of a high suspicion on clinical grounds, in which they appear like heterogeneous encapsulated masses.[] Surgical excision of the mass followed by pathological examination remains the modality of treatment of these tumors. Surgical exploration of the inguinal canal will differentiate round ligament leiomyoma from the incarcerated inguinal hernia and inguinal lymphadenopathy.[] In summary, extraperitoneal round ligament leiomyomas is a rare entity usually presenting as right-sided inguinal swellings and should be considered as one of the differential diagnoses of the more common inguinal hernia, especially in a female patient. An MRI may aid preoperatively in characterizing this lesion, but surgical excision and pathological examination remain the gold standard. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

- 1. Christodoulou IM, Angelopoulos A, Siaperas P, Ioannidis A, Skarpas A, Tellos A, et al Leiomyoma of the round ligament of the uterus mimicking inguinal hernia Case Rep Surg. 2018;2018:6702494 - 2. Colak E, Ozlem N, Kesmer S, Yildirim K. A rare inguinal mass: Round ligament leiomyoma Int J Surg Case Rep. 2013;4:577–8 - 3. Ryan GL, Syrop CH, Van Voorhis BJ. Role, epidemiology, and natural history of benign uterine mass lesions Clin Obstet Gynecol. 2005;48:312–24 - 4. Birge O, Arslan D, Kinali E, Bulut B. Round ligament of uterus leiomyoma: An unusual cause of dyspareunia Case Rep Obstet Gynecol. 2015;2015:197842 - 5. Bhosale PR, Patnana M, Viswanathan C, Szklaruk J. The inguinal canal: Anatomy and imaging features of common and uncommon masses Radiographics. 2008;28:819–35 - 6. Efthimiadis C, Ioannidis A, Grigoriou M, Kofina K, Gerasimidou D. Leiomyoma of round ligament mimicking an incarcerated inguinal hernia-report of a rare case J Surg Case Rep. 2017;2017:Rjx237 - 7. Ali SM, Malik KA, Al-Qadhi H, Shafiq M. Leiomyoma of the round ligament of the uterus: Case report and review of literature Sultan Qaboos Univ Med J. 2012;12:357–9 - 8. Harish E, Sowmya NS, Indudhara PB. A rare case of round ligament leiomyoma: An inguinal mass J Clin Diagn Res. 2014;8:NJ05–6