Andrew Galffy and Christopher Morosky
History of present illness
A 45-year-old gravida 3, para 1 woman presents to the office for an annual gynecologic examination and routine screening.
She reports that over the past three months she has noticed increasing pressure in the vagina and worsening pain with intercourse. She denies menstrual irregularities, urinary frequency, hesitancy or dribbling, dysuria, dyspareunia, or abnormal vaginal discharge.
Her previous medical history is significant for obesity and hypothyroidism. She takes 100μg of levothyroxine PO every day. Her previous surgical history includes a postpartum bilateral tubal ligation and two prior dilation and curettage procedures. Her obstetrical history includes a first-trimester termination of pregnancy, afirst-trimester spontaneous abor- tion, and a term normal spontaneous vaginal delivery. All of her previous Pap smears and mammograms have been normal.
She denies a history of sexually transmitted infections.
Physical examination
General appearance:Obese woman in no apparent distress Vital signs:
Temperature: 36.8°C Pulse: 82 beats/min
Blood pressure: 122/82 mmHg Respiratory rate: 16 breaths/min Oxygen saturation: 99% on room air
Cardiovascular:Regular rate and rhythm without murmurs, rubs, or gallops
Lungs:Clear to auscultation bilaterally
Abdomen:Soft, nontender and nondistended, no guarding or rebound, normal active bowel sounds
External genitalia:Normal appearing with no lesions, masses, or discoloration
Vagina:An approximately 4-cm smooth, mobile, nontender mass is palpable in the anterior vaginal wall. The mass is moderatelyfirm, and compression does not produce a discharge from the urethral meatus. There is no distortion of the surrounding structures. On visual inspection, the vaginal epithelium covering the mass is without abnormality (Fig. 84.1)
Cervix:Easily visualized past the anterior vaginal wall mass.
Normal in appearance
Uterus:Normal sized and anteverted Adnexa:Nontender and without masses
Imaging:A T2-weighted contrast MRI of the pelvis reveals a 4.1 × 4.2 cm mass located within the anterior vaginal wall.
The mass is clearly separated from the urethra and has homogenous enhancement (Fig. 84.2)
Acute Care and Emergency Gynecology, ed. David Chelmow, Christine R. Isaacs and Ashley Carroll. Published by Cambridge University Press.
© Cambridge University Press 2015.
Fig. 84.1 A 4 cm anterior vaginal wall mass that isfirm and nontender.
Fig. 84.2 A T2-weighted MRI of the pelvis shows the anterior vaginal wall mass.
How would you manage this patient?
The patient has an extrauterine leiomyoma located in the anterior vaginal wall. She underwent a transvaginal excision with layered closure. Histologic examination revealed inter- lacing bundles of benign smooth muscle cells. Due to the proximity of the urethra to the area of excision, the patient wore an indwelling catheter for two weeks to prevent urethro- vaginalfistula formation. At her four-week follow-up visit she was completely healed and without complication.
Periurethral masses
Symptomatic periurethral masses are an uncommon occur- rence. Description of their workup and management in the literature is mostly limited to case reports or case series [1].
There are a number of pathologic conditions within this ana- tomic area that may give rise to a periurethral mass and may cause patients to present with a variety of symptoms. Often, however, the clinician mayfind a mass through palpation of the anterior vaginal wall during the routine physical examin- ation of an asymptomatic patient.
The differential diagnosis of a periurethral mass can be divided into three major categories [2]. The first category is anterior vaginal wall prolapse. Prolapse is a common condi- tion, especially in parous patients. Typically, patients with anterior vaginal wall prolapse present with the complaint of a bulge in the vagina that is worse with increased intra- abdominal pressure or prolonged standing. These patients commonly have some degree of stress urinary incontinence.
Physical examination reveals prolapse along the entire anterior vaginal wall that is worsened with Valsalva techniques.
A discrete periurethral mass is seldom encountered in the patient with prolapse.
Conditions specific to the urethra and urologic system are the next category and include urethral diverticulum, periure- thralfibrosis, ectopic ureterocele and Skene’s gland abscesses.
These patients will commonly have some degree of urinary symptoms, including dysuria, frequency, hesitancy, incomplete emptying or dribbling of urine. Compression of the periure- thral mass often results in expression of urine or purulent material from the urethra. This maneuver has been termed,
“milking the urethra.”
The final category is benign and malignant neoplasms arising from the vagina and urethra. These include vaginal leiomyoma, vaginal wall inclusion cysts, Gartner’s duct cysts, vaginal cancer and urethral cancer. The combination of a periurethral mass and bloody discharge from the urethra should raise the suspicion for a malignant condition. These patients should be worked-up in collaboration with a gyneco- logic or urologic oncologist. The discovery of any periurethral mass warrants further investigation because although most periurethral masses are of benign etiology, proper diagnosis is essential for management decisions.
When beginning the diagnostic workup, the initial presen- tation of the patient will often aid in exclusion of many of the
pathologies listed above. For instance, in the case of our patient she reported increased vaginal pressure and dyspareunia, however she had no complaints of bleeding, discharge, dysuria or incontinence. Also the mass wasfirm, smooth, and mobile, which suggests a solid and not cystic mass. The fact that it was smooth and mobile also reduces the chance of it being malignant. While these findings are extremely informative, additional workup is needed due to the diversity of the differ- ential diagnosis and the relatively low incidence of most of the conditions on our list.
The next step is to obtain an imaging study that will most effectively aid in obtaining the diagnosis and therefore plan- ning the appropriate management. The most efficient imaging modality to start with when working up a discrete periurethral mass is generally ultrasound. Even when suspicion for urethral diverticulum, the most common discrete periurethral mass, is high, voiding cystourethrography (VCUG) and retrograde positive pressure urethrography are no longer recommended for routine evaluation due to their low sensitivity, exposure to radiation, and lack of providing additional information [3,4,5].
A study comparing ultrasound to VCUG found that both techniques were able to diagnose 13 of 15 urethral diverticula, however ultrasound was also able to diagnose periurethral cysts and leiomyomas not detected by VCUG [6].
The most effective imaging modality available to diagnose periurethral masses is MRI. Some authors argue that MRI should always be the first-line imaging modality despite its increased expense and limited availability when compared to ultrasound [7]. When the mass is evidently solid, MRI is a reasonable initial choice as it can substantially aid not only in diagnosis but also surgical planning. MRI provides multipla- nar resolution lending superior tissue resolution and allows for differentiation between normal anatomic variants, soft tissue masses, and urethral pathology. The MRI findings of our patient showed that the mass was located within the anterior vaginal wall and clearly separated from the urethra with homo- genous enhancement. The decision was made to excise the mass so as to obtain a pathologic diagnosis.
The histologic evaluation revealed interlacing bundles of benign smooth muscle cells consistent with a leiomyoma.
While the vast majority of leiomyoma are found within the uterine corpus, the rare appearance of extrauterine leiomyo- mas is occasionally encountered. Extrauterine leiomyomas have been noted to present in various ways: benign metastasiz- ing, parasitic, intravenous leiomyomatosis, leiomyomatosis peritonealis disseminata, and other miscellaneous locations have been reported [8,9]. In general, leiomyomas with rare growth patterns tend to be found in women of reproductive age, often with a history of uterine surgery. It is still unclear if these tumors occur from hematogenous spread of smooth muscle cells from the uterus or if they arise from proliferation of smooth muscle cells in the extrauterine location.
Surgery should be performed by an experienced vaginal surgeon whenever in close proximity to the urethra due to the concern of urethral injury and subsequent urethrovaginal
fistula formation following such procedures. The use of a layered closure when repairing the incision is used to reduce the risk of fistula formation and prevent stricture that can cause urethral obstruction. In certain cases where large exci- sions are required, the use of interpositionalflaps or grafts may be required. In addition, the use of a transurethral indwelling catheter for two weeks can prevent urethrovaginalfistula for- mation and urethral stricture.
Key teaching points
Periurethral masses can present with a broad range of symptoms including urinary complaints, pain with intercourse, or a bulge or pressure in the vagina. However, many patients may be asymptomatic when they are discovered to have a periurethral mass on routine examination.
Abnormal variants of the distal urologic tract can present as distinct periurethral masses. These include urethral diverticulum, periurethralfibrosis, ectopic ureterocele, and Skene’s gland abscesses.
Both malignant and benign neoplasms can arise from the periurethral tissues. The combination of an enlarging periurethral mass and bloody urethral discharge should raise the concern for malignancy.
Both transvaginal ultrasonography and MRI are superior to voiding cystourethrography in diagnosing the etiology of periurethral masses.
Periurethral leiomyomas are a rare but recognized unusual location tofind extrauterinefibroids. Their treatment entails surgical excision with layered closure. Care must be taken to avoid urethrovaginalfistulas and urethral stricture following excision.
References
1. Blaivas JG, Flisser AJ, Bleustein CB, Panagopoulos G. Periurethral masses:
Etiology and diagnosis in a large series of women.Obstet Gynecol2004;
103(5 Pt 1):842–7.
2. Dmochowski RR, Ganabathi K, Zimmern PE, Leach GE. Benign female periurethral masses.J Urol1994;
152(6 Pt 1):1943–51.
3. Golomb J, Leibovitch I, Mor Y, Morag B, Ramon J. Comparison of voiding cystourethrography and double-balloon urethrography in the diagnosis of complex female
urethral diverticula.Eur Radiol2003;
13(3):536–42.
4. Jacoby K, Rowbotham RK. Double balloon positive pressure urethrography is a more sensitive test than voiding cystourethrography for diagnosing urethral diverticulum in women.J Urol 1999;162(6):2066–9.
5. Lee JW, Fynes MM. Female urethral diverticula.Best Pract Res Clin Obstet Gynaecol2005;19(6):875–93.
6. Siegel CL, Middleton WD, Teefey SA, et al. Sonography of the female urethra.
Am J Roentgenol1998;170(5):
1269–74.
7. Shadbolt CL, Coakley FV, Qayyum A, Donat SM. MRI of vaginal leiomyomas.
J Comput Assist Tomogr2011;25(3):
355–7.
8. Fasih N, Shanbhogue A, Macdonald DB, et al. Leiomyomas beyond the uterus: Unusual locations, rare manifestations.RadioGraphics 2008;28:1931–48.
9. Quade BJ, Robboy SJ. Uterine smooth muscle tumors. In Robboy SJ, Mutter GL, Prat J, et al., eds.Robboy’s Pathology of the Female Reproductive Tract, 2nd edn. Oxford, Churchill Livingstone Elsevier, 2009, p. 474.
Case 84: A periurethral mass in a 45-year-old woman