Case report
Year : 2013 Month : April Volume : 2 Issue : 1 Page : 22 - 24 Full Version

Anterior Wall Urethral Leiomyoma of the Distal Urethra – A Case Report
Mary Mathew, Bhavna Nayal, Sumeet Kaur Dil, Joseph Thomas
1. Professor of Pathology, 2. Assistant Professor of Pathology, 3. Associate Professor of Pathology, 4. Professor of Urology, KMC, Manipal University, Manipal, India.
 
Correspondence Address :
Mary Mathew, Bhavna Nayal, Sumeet Kaur Dil, Joseph Thomas,
Dr. Bhavna Nayal,
Assistant Professor, Department of Pathology,
Kasturba Medical College, Manipal, Manipal University,
India.
Ph: +919900411064
Email: bhavnayal17@gmail.com
 
ABSTRACT
: Urethral leiomyomas are uncommon smooth muscle lesions usually affecting the proximal segment and the anterior wall of the urethra. These lesions are cured by simple excision. We present a 35-year-old lady with urethral leiomyoma of the distal portion of the urethra arising from the anterior wall and presenting as mass per urethra. The patient was treated by surgical excision and there was no recurrence on follow up.
Keywords : Benign, Urethra, Distal, Anterior wall, Tumour
DOI and Others :
 
INTRODUCTION
Urethral leiomyomas are rare benign lesions arising from the smooth muscle of the urethra and are more frequent in females (1). They present with symptoms of repeated lower urinary tract infection and voiding difficulties (2). These lesions tend to occur more frequently in the posterior wall and in the proximal segment of the urethra (2),(3). Very few cases of urethral leiomyomas have been reported in literature. We present a 35 year old woman with leiomyoma involving the anterior wall of the distal urethra manifesting as with mass per urethra of 7 years duration.
 
 
Case Report
A 35 years old female presented with urinary stress incontinence and mass per urethra since 7 years. She gave a history of bleeding during sexual intercourse. There was no history of haematuria or dysuria. Urine examination was normal. Cystoscopy showed normal proximal urethra and vesical interior. There was no clinical or radiographical evidence of leiomyoma elsewhere in the patient. The mass was excised under general anaesthesia. Intra-operatively, a pedunculated growth, measuring 4x3cm was seen arising from the anterior wall of the distal urethra. The proximal urethra was normal. The excised mass was sent for histopathological examination. Gross examination revealed an encapsulated nodular mass measuring 4x3x1cm. Cut section showed grey white whorled areas (Table/Fig 1). On microscopy, squamous epithelium with submucosal lymphoid follicles was seen overlying an encapsulated well circumscribed tumor composed of interlacing bundles and fascicles of spindle shaped smooth muscle cellswith areas of hyalinization (Table/Fig 2). There was no mitotic figure or coagulative necrosis. A diagnosis of leiomyoma was rendered.

 
 
Discussion
Leiomyoma is a benign neoplasm of the soft tissue, commonly affecting genitourinary and gastrointestinal tract (4). In the urinary tract, kidney and bladder are the most common sites of this tumour. However, urethral leiomyomas are very rare (2),(3). They usually arise from the posterior wall and proximal segment of the urethra with preponderance for women in the reproductive age group (3),(5). The present case was different as the lesion involved the anterior wall the distal urethra. Hormones such as estrogen and progesterone play a role in the development of leiomyoma as they enlarge during pregnancy and regress following delivery. The exact origin of this tumor is unknown and paraurethral leiomyomas have been documented in postmenopausal women as well (3),(6),(7). The most common clinical manifestation in urethral leiomyoma is repeated urinary tract infection and irritative symptoms. Rarely, it presents with mass per vagina, dyspareunia, dysuria and hematuria (3), (6). Perera et al., reported a case presenting as a labial mass with intra-abdominal extension (5). Our case was a female patient in the reproductive age group presenting with stress incontinence and mass per vagina. There was no history of lower urinary tract infection.

Differential diagnosis of urethral leiomyoma includes benign lesions like urethral caruncle, diverticulum, urethrocele and malignancies such as leiomyosarcoma, lymphoma and plasmacytoma. Uretheral leiomyomas should also be distinguished from paraurethral myomas as they can also present with similar complaints, however, these lesions can be excised without damaging urtheral mucosa or muscle (5),(8),(9). A thorough clinical examination, urethroscopy, radiological along with microscopic examination aids in the diagnosis of this lesion (1), (3). Microscopically, these tumours are characterized by intersecting fascicles of well differentiated smooth muscle cells. Secondary changes like hyalinization, myxoid change, calcification and fatty change may be present in the stroma (4). Absence of cellular pleomorphism, nuclear atypia, mitosis and necrosis rules out malignancy in the present case. The treatment of choice for urethral leiomyoma is surgical excision per vagina. However, large tumours require transabdominal approach. Intraoperative damage to the urethral mucosa during tumour excision may lead to complications such as stress incontinence or urethral stenosis. Therefore, any mucosal damage should be repaired (3), (5).

Urethral leiomyomas have an excellent prognosis. These tumors usually do not recur following excision, nor do they undergo malignant transformation. However, a case with recurrence was reported in a patient with tumor size of more than 8 cm (3). After five months of follow up, our patient is asymptomatic.
 
 
Conclusion
Urethral leiomyomas are rare benign neoplasm of deep soft tissue with very good prognosis. These tumors may cause long standing symptoms and can be cured completely be simple local excision. Hence, the surgeons should entertain leiomyoma as a differential diagnosis in a patient with urinary disturbance.
 
REFERENCES
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TABLES AND FIGURES