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Leiomyoma of the extraperitoneal round ligament
LEIOMYOMA OF THE EXTRAPERITONEAL ROUND LIGAMENT: CT DEMONSTRATION DAVID M. WARSHAUER, MD, AND STANLEY R. MANDEL, MD
We report the computed tomography (CT) description of a leiomyoma involving the extraperitional portion of the round ligament. Although unusual, such a lesion may mimic other mass lesions in this vicinity including adenopathy, endometriomas, and inguinal hernias. Elsevier Science Inc., 2000 KEY WORDS:
Round ligament; Leiomyoma; Computed tomography
INTRODUCTION The round ligament extends from the uterus through the inguinal canal to terminate in the region of the mons pubis and labia majora. Embryologically it is the female equivalent of the gubernaculum testis and is composed predominantly of smooth muscle fibers, connective tissue, vessels and nerves with a mesothelial coating (1). In this report we present, to our knowledge, the first computed tomography (CT) description of a leiomyoma arising from the inguinal portion of the round ligament and mimicking adenopathy. CASE REPORT A 63-year-old female presented with a complaint of intermittent right groin pain for several months. On physical exam a firm, slightly tender 2-cm mass was felt in the region of the right inguinal canal. The mass From the Department of Radiology (D.M.W.) and the Department of Surgery (S.R.M.), University of North Carolina, Chapel Hill, North Carolina. Address correspondence to: David M. Warshauer, MD, Dept. of Radiology, Campus Box 7510, University of North Carolina School of Medicine Chapel Hill, N.C. 27599-7510. Tel: 919 9663086; E-mail: [email protected] Received January 12 1997; accepted February 16, 1998. CLINICAL IMAGING 1999;23:375–376 Elsevier Science Inc., 2000. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
was intermittently reducible and not accompanied by gastrointestinal obstructive symptoms. She had a history of surgical excision of a malignant melanoma (Clark level III) from the right lower extremity 22 years previously. An inguinal node dissection performed at that time had revealed no evidence of metastatic disease. She had also undergone a hysterectomy for fibroids over 20 years ago. The patient’s medications included conjugated estrogen for postmenopausal symptoms and hydrochlorothiazide and atenolol for hypertension. Because of concern that the right inguinal mass could represent a late melanoma metastatis rather than a simple reducible inguinal hernia, a contrastenhanced abdominal pelvic CT scan was performed. Images of the inguinal region demonstrated a 3 cm ⫻ 2 cm slightly hetergeneous enhancing mass in the right inguinal region (Figure 1). This did not extend into the peritoneal cavity and did not communicate with bowel or other structures. No additional masses were noted nor was adenopathy appreciated in the remainder of the pelvis or abdomen. The patient was brought to surgery for removal of the mass and/or right inguinal hernia repair. At surgery the mass appeared well circumscribed and was attached to the extraperitoneal round ligament by a short pedicle. On gross pathologic examination the cut surface was white with a whorled appearance. Microscopic examination showed a benign spindle cell neoplasm consistent with a leiomyoma.
DISCUSSION Tumors involving the round ligament are unusual. Leiomyomas are the most common lesion with endometriomas and mesothelial cysts next in frequency (2–4). Approximately one-half to two-thirds of leiomyomas occur in the extraperitoneal portion of the 0899-7071/99/$–see front matter PII S0899-7071(98)00021-7
376
WARSHAUER AND MANDEL
FIGURE 1. Contrast-enhanced axial CT demonstrates an enhancing, somewhat heterogeneous mass in the proximal portion of the right inguinal canal (arrow).
round ligament and are more common on the right for unclear reasons. Although usually single and unilateral, they can be multiple and bilateral. The average size of the lesions ranges from 3 to 5 cms. Intraabdominal round ligament leiomyomas are usually asymptomatic, with extraperitoneal lesions presenting as small masses (2). The lesion and presentation in our patient was similar to those described in the literature. The occurrence of a round ligament leiomyoma in this patient may have been related to her propensity for uterine fibroids as shown by her earlier hysterectomy. In 50% of reported cases lesions are associated with uterine leiomyomas (2). Estrogen use may also have contributed to the formation of the leiomyoma as estrogen and progesterone receptors have been noted in round ligament smooth muscle (5). Mass lesions involving the extraperitoneal portion of the round ligament as it courses through the inguinal canal can mimic an incarceated hernia or adenopathy. Preoperative imaging may be helpful in dif-
CLINICAL IMAGING VOL. 23, NO 6
ferential diagnosis but is rarely used prior to surgical exploration. The imaging appearance of endometriomas (6), mesenteric cysts (7), and varices (8) involving the extraperitoneal round ligament have been reported. We can find no prior CT description of extraperitoneal round ligament leiomyomas. The appearance noted in this case of a well circumscribed lesion with fairly bright but somewhat heterogeneous enhancement is nonspecific but typical of leiomyomas. The solid enhancing nature of the lesion would distinguish it from mesenteric and endometrial cysts. Although bright enhancement could also be noted in femoral pseudoaneurysm and in round ligament varices, the lack of communication with the femoral artery and proximal extension excludes these diagnosis. Metastatic adenopathy however, could have this appearance and requires pathologic examination for exclusion. REFERENCES 1. Williams PL, Worwick R. Dyson M, Bannister LH. (eds). Grey’s Anatomy. 37th edition. New York: Churchill Livingston, 1989. 2. Breen JL, Neubecker RD. Tumors of the round ligament. A review of the literature and a report of 25 cases. Obstet Gynecol 1962;19:771–780. 3. Candiani GB, Vercellini P, Fedele L, Vendola N, Carinelli S, Scaglione V. Inguinal endometriosis: pathogenetic and clinical implications. Obstet Gynecol 1991;78(2):191–194. 4. Harper GB Jr, Awbrey BJ, Thomas CG Jr, Askin FB. Mesothelial cysts of the round ligament simulating inguinal hernia. Report of four cases and a review of the literature. Am J Surg 1986; 151(4):515–517. 5. Smith P, Heimer G, Norgren A, Ulmsten U. The round ligament: a target organ for steroid hormones. Gynecol Endocrinol 1993;7(2):97–100. 6. Freed KS, Granke DS, Tyre LL, Williams VL, Omert LA. Endometriosis of the extraperitoneal portion of the round ligament: US and CT findings. J Clin Ultrasound 1996;24(9):540–542. 7. Berna JD, Garcia-Medina V, Guirao J, Madrigal M. Mesothelial cyst of the round ligament. Am J Roentgenol 1990;155(6): 1345–1346. Letter. 8. Cheng D, Lam H, Lam C. Round ligament varices in pregnancy mimicking inguinal hernia: an ultrasound diagnosis. Ultrasound Obstet Gynecol 1997;9(3):198–199.
We report the computed tomography (CT) description of a leiomyoma involving the extraperitional portion of the round ligament. Although unusual, such a lesion may mimic other mass lesions in this vicinity including adenopathy, endometriomas, and inguinal hernias. Elsevier Science Inc., 2000 KEY WORDS:
Round ligament; Leiomyoma; Computed tomography
INTRODUCTION The round ligament extends from the uterus through the inguinal canal to terminate in the region of the mons pubis and labia majora. Embryologically it is the female equivalent of the gubernaculum testis and is composed predominantly of smooth muscle fibers, connective tissue, vessels and nerves with a mesothelial coating (1). In this report we present, to our knowledge, the first computed tomography (CT) description of a leiomyoma arising from the inguinal portion of the round ligament and mimicking adenopathy. CASE REPORT A 63-year-old female presented with a complaint of intermittent right groin pain for several months. On physical exam a firm, slightly tender 2-cm mass was felt in the region of the right inguinal canal. The mass From the Department of Radiology (D.M.W.) and the Department of Surgery (S.R.M.), University of North Carolina, Chapel Hill, North Carolina. Address correspondence to: David M. Warshauer, MD, Dept. of Radiology, Campus Box 7510, University of North Carolina School of Medicine Chapel Hill, N.C. 27599-7510. Tel: 919 9663086; E-mail: [email protected] Received January 12 1997; accepted February 16, 1998. CLINICAL IMAGING 1999;23:375–376 Elsevier Science Inc., 2000. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
was intermittently reducible and not accompanied by gastrointestinal obstructive symptoms. She had a history of surgical excision of a malignant melanoma (Clark level III) from the right lower extremity 22 years previously. An inguinal node dissection performed at that time had revealed no evidence of metastatic disease. She had also undergone a hysterectomy for fibroids over 20 years ago. The patient’s medications included conjugated estrogen for postmenopausal symptoms and hydrochlorothiazide and atenolol for hypertension. Because of concern that the right inguinal mass could represent a late melanoma metastatis rather than a simple reducible inguinal hernia, a contrastenhanced abdominal pelvic CT scan was performed. Images of the inguinal region demonstrated a 3 cm ⫻ 2 cm slightly hetergeneous enhancing mass in the right inguinal region (Figure 1). This did not extend into the peritoneal cavity and did not communicate with bowel or other structures. No additional masses were noted nor was adenopathy appreciated in the remainder of the pelvis or abdomen. The patient was brought to surgery for removal of the mass and/or right inguinal hernia repair. At surgery the mass appeared well circumscribed and was attached to the extraperitoneal round ligament by a short pedicle. On gross pathologic examination the cut surface was white with a whorled appearance. Microscopic examination showed a benign spindle cell neoplasm consistent with a leiomyoma.
DISCUSSION Tumors involving the round ligament are unusual. Leiomyomas are the most common lesion with endometriomas and mesothelial cysts next in frequency (2–4). Approximately one-half to two-thirds of leiomyomas occur in the extraperitoneal portion of the 0899-7071/99/$–see front matter PII S0899-7071(98)00021-7
376
WARSHAUER AND MANDEL
FIGURE 1. Contrast-enhanced axial CT demonstrates an enhancing, somewhat heterogeneous mass in the proximal portion of the right inguinal canal (arrow).
round ligament and are more common on the right for unclear reasons. Although usually single and unilateral, they can be multiple and bilateral. The average size of the lesions ranges from 3 to 5 cms. Intraabdominal round ligament leiomyomas are usually asymptomatic, with extraperitoneal lesions presenting as small masses (2). The lesion and presentation in our patient was similar to those described in the literature. The occurrence of a round ligament leiomyoma in this patient may have been related to her propensity for uterine fibroids as shown by her earlier hysterectomy. In 50% of reported cases lesions are associated with uterine leiomyomas (2). Estrogen use may also have contributed to the formation of the leiomyoma as estrogen and progesterone receptors have been noted in round ligament smooth muscle (5). Mass lesions involving the extraperitoneal portion of the round ligament as it courses through the inguinal canal can mimic an incarceated hernia or adenopathy. Preoperative imaging may be helpful in dif-
CLINICAL IMAGING VOL. 23, NO 6
ferential diagnosis but is rarely used prior to surgical exploration. The imaging appearance of endometriomas (6), mesenteric cysts (7), and varices (8) involving the extraperitoneal round ligament have been reported. We can find no prior CT description of extraperitoneal round ligament leiomyomas. The appearance noted in this case of a well circumscribed lesion with fairly bright but somewhat heterogeneous enhancement is nonspecific but typical of leiomyomas. The solid enhancing nature of the lesion would distinguish it from mesenteric and endometrial cysts. Although bright enhancement could also be noted in femoral pseudoaneurysm and in round ligament varices, the lack of communication with the femoral artery and proximal extension excludes these diagnosis. Metastatic adenopathy however, could have this appearance and requires pathologic examination for exclusion. REFERENCES 1. Williams PL, Worwick R. Dyson M, Bannister LH. (eds). Grey’s Anatomy. 37th edition. New York: Churchill Livingston, 1989. 2. Breen JL, Neubecker RD. Tumors of the round ligament. A review of the literature and a report of 25 cases. Obstet Gynecol 1962;19:771–780. 3. Candiani GB, Vercellini P, Fedele L, Vendola N, Carinelli S, Scaglione V. Inguinal endometriosis: pathogenetic and clinical implications. Obstet Gynecol 1991;78(2):191–194. 4. Harper GB Jr, Awbrey BJ, Thomas CG Jr, Askin FB. Mesothelial cysts of the round ligament simulating inguinal hernia. Report of four cases and a review of the literature. Am J Surg 1986; 151(4):515–517. 5. Smith P, Heimer G, Norgren A, Ulmsten U. The round ligament: a target organ for steroid hormones. Gynecol Endocrinol 1993;7(2):97–100. 6. Freed KS, Granke DS, Tyre LL, Williams VL, Omert LA. Endometriosis of the extraperitoneal portion of the round ligament: US and CT findings. J Clin Ultrasound 1996;24(9):540–542. 7. Berna JD, Garcia-Medina V, Guirao J, Madrigal M. Mesothelial cyst of the round ligament. Am J Roentgenol 1990;155(6): 1345–1346. Letter. 8. Cheng D, Lam H, Lam C. Round ligament varices in pregnancy mimicking inguinal hernia: an ultrasound diagnosis. Ultrasound Obstet Gynecol 1997;9(3):198–199.