Three female patients with a periurethral mass: from various complaints to rare pathology

Abstract

In this case report, we will discuss three cases of women diagnosed with a periurethral mass. The specific diagnosis of a periurethral mass can vary and includes rare diseases. Therefore, they provide a challenge to medical professionals. All patients underwent diagnostic evaluation with cystoscopy and pelvic MRI followed by surgical removal. Based on the MRI and pathology report, different diagnoses were made for each patient. The three diagnoses will be discussed: subpubic cartilaginous cyst, leiomyoma and clear cell adenocarcinoma of the urethra. Our case report is useful for other medical professionals, and they can evaluate how to optimal approach a periurethral mass.

Background

When a urologist or gynaecologist discovers a periurethral mass, they cannot rely on standard procedure and will have to use their expertise to choose the optimal approach. This can be challenging, since the symptoms, physical examination and differential diagnosis of periurethral masses are diverse. The wide range of complaints that patients can present with poses a challenge. These range from asymptomatic to lower urinary tract symptoms or acute urinary retention.¹ Clear results after conducting physical examination and a cystoscopy are not always present. Therefore, periurethral masses can be complex to diagnose and may sometimes not be diagnosed at all.² In 2004, Blavais et al¹ reported the differential diagnosis of periurethral masses extracted from a patient database of a private urology practice specialised in female urology. In the patient database of 1950 women, 79 women with periurethral masses were identified. The most common diagnosis was a urethral diverticulum (84%). Ninety-seven per cent of the urethral diverticula were seen on voiding cystourethrogram, which were all preformed to evaluate refractory lower urinary tract symptoms. Other diagnoses included a vaginal cyst, leiomyoma, ectopic urethrocele, vaginal squamous cell carcinoma and infected granuloma (table 1).

Table 1.

Overview of 79 women with periurethral masses and their diagnosis (%)

Diagnosis	Percentage of women (n=79)
Urethral diverticula	84
Vaginal cyst	7
Leiomyoma	5
Ectopic urethrocele	2.5
Vaginal squamous cell carcinoma	2.5
Infected granuloma	1

Additionally, the differential diagnosis also includes Skene’s gland cyst or abscess, urethral prolapse, urethral caruncle and Gartner’s duct cyst.³ Pelvic MRI remains the method of choice for diagnosing female urethral and periurethral pathologies.⁴ MRI provides useful information regarding the morphological and structural characteristics of the mass. In this case report, we will discuss three cases of women with a periurethral mass.

Case presentation

Case 1: a 68-year-old woman with lower urinary tract symptoms was referred by her general practitioner. She underwent an abdominal hysterectomy 25 years prior. For the past 2 months, the patient had experienced a weak urinary flow and incomplete bladder emptying, nycturia and one single event of macroscopic haematuria. On physical examination, an immobile solid mass was palpable on the ventral wall of the vagina. The meatus was shifted dorsally into the vagina. Cystoscopy showed no urethral or intravesical abnormalities. The pelvic MRI noted a partly solid and partly cystic degenerative lesion originating from the symphysis. The lesion measured 3.2 cm × 3.8 cm and had a mass effect on the urethra (figure 1A). The radiologist defined this as a benign mass. During surgery, the mass appeared to be semisolid and firmly adherent to the inner rim of the symphysis pubis. An accurate surgical plane could not be established; a subtotal resection was performed during which the mass was ‘opened’. The mass was partially filled with a translucent fluid. It turned to solid mass in the vicinity of the pubic bone. The pathology report confirmed the diagnosis proposed by the radiologist.

Figure 1.

Axial and sagittal T2-weighted MRI images from the three patients. First row=case 1; second row=case 2; third row=case 3. Red arrow indicates the periurethral mass.

Case 2: a 48-year-old woman was referred from the gynaecology department for evaluation of a periurethral mass. The patient had symptoms of urinary frequency and urgency. Physical examination revealed a mobile elastic solid mass palpable on the ventral wall of the vagina. Initially, it was mistaken for an anterior wall prolapse. Cystoscopy revealed no urethral or intravesical abnormalities. The pelvic MRI noted a round lesion originating from the urethra of 3.7 cm in diameter, suggesting a leiomyoma of the urethra (figure 1B). The patient underwent a transvaginal excision of the lesion. During surgery, the mass could easily be shifted into the introitus of the vaginal canal. After placement of a transurethral catheter, a paraurethral incision was made, and the mass could effortlessly be dissected and removed completely. The established diagnosis by the radiologist was confirmed with the pathology report: a benign paraurethral leiomyoma.

Case 3: a 40-year-old woman was referred from the gynaecology department for evaluation of a palpable periurethral mass. The patient had no lower urinary tract symptoms. Physical examination showed a 3 cm mobile elastic solid mass palpable on the ventral wall of the vagina. Cystoscopy revealed no urethral or intravesical abnormalities. The pelvic MRI showed a tumour of 2.7 cm × 2.2 cm anterolaterally right of the vagina (figure 1C). The solid mass had sharp boundaries, with no connection to the urethra or surrounding structures. The radiologist offered a wide differential diagnosis of leiomyoma, chronic infected Gartner’s duct cyst, urethral carcinoma, neurofibroma or angioma. The patient underwent a transvaginal excision of the lesion. During surgery, the mass appeared as a thin-walled cyst, which strongly adhered to its surrounding. The cyst was opened, and liquid fluid was spilled. An accurate surgical plane could not be established, so the mass was excised blindly. The pathology report revealed a clear-cell adenocarcinoma of the urethra (CCAU) derived from the Müllerian or Wolffian remnants or Skene’s gland. Pathological radicality was unsure, and the patient was referred to a tertiary cancer centre.

The patient characteristics are summarised in table 2.

Table 2.

Patient characteristics of the three different cases

	Age	Gender	Reason for polyclinic visit	Physical exam	Cystoscopy	Pathology report
1	68 years	Female	Weak urinary flow, incomplete bladder emptying, nycturia and macroscopic haematuria.	Palpable immobile solid mass on the ventral wall of the vagina and shift of meatus dorsally into the vagina.	Normal.	Subpubic cartilaginous cyst.
2	48 years	Female	Referred from gynaecologist with palpable mass and frequency and urgency.	Palpable mobile elastic solid mass on the ventral wall of the vagina.	Normal.	Leiomyoma.
3	40 years	Female	Referred from gynaecologist with palpable mass.	Palpable 3 cm mobile elastic solid mass on the ventral wall of the vagina.	Normal.	Clear cell adenocarcinoma of the urethra.

Outcome and follow-up

All patients were seen in the outpatient clinic after the surgery. During this appointment, the outcome of the pathology report was discussed, and the complaints were evaluated.

Case 1: during the follow-up, the patient was asymptomatic. Follow-up was for a period of a year.

Case 2: Patient was only seen once after surgery; the patient’s symptoms have been resolved.

Case 3: Patient was referred to a tertiary cancer centre, were they preformed the follow-up. Directly after surgery, PET CT scan revealed no lymphogenic metastasis, so the patient received additional radiotherapy of 60 Gy in 30 sessions. The patient had strict follow-up, which included abdominal CT scans. Two years after initial treatment, abdominal CT scan showed a suspect lymph node of 3.5 cm next to arteria iliaca communis dextra. After excision, pathology report revealed a metastasis of CCAU. The pelvic MRI did not reveal local recurrence paraurethral. The patient did not receive adjuvant chemotherapy or additional radiotherapy. Five years after the initial procedure, there was no evidence of tumour recurrence.

Discussion

In these three cases, completely different diagnoses were made based on the pelvic MRI and the pathology report. In the first case, a subpubic cartilaginous cyst was found. This is a benign and rare cystic lesion related to the pubic symphysis. A subpubic cartilaginous cyst has only been reported in 20 other cases.^{5 6} Patients have experienced a variety of symptoms. Approximately a third of the patients had a painless lump, with urinary symptoms, such as incomplete bladder emptying or acute urinary retention.^{5 6} Other patients experienced chronic abdominal pain, a painful mass with sharp vaginal or penile/scrotal pain, dyspareunia and difficult (initiating) micturition.^{5 6} One patient did not have any symptoms at all.⁵ In the second case, the paraurethral mass was leiomyoma, originating from the smooth muscle layer surrounding the urethra. Leiomyomata are mesenchymal tumours that can develop from smooth muscle cells. Most common are uterine leiomyomata, although these can originate from other genitourinary locations, like the urethra, renal pelvis, ureter, bladder wall, prostate, spermatic cord, vas deferens, epididymis and seminal vesicle.^{7 8} Patients suffering from paraurethral leiomyomata will exhibit different symptoms, according to the location and size of the paraurethral leiomyomata. When small, these are usually asymptomatic; however, as they grow, symptoms vary from voiding difficulties with recurrence urinary tract infections, pain, irritative symptoms, haematuria, palpable mass, dysuria, dyspareunia and urinary retention.^7–11 Leiomyomata are benign tumours, and no malignant transformations were reported.^{9 11} In the third case, final pathology revealed a CCAU, which is a very rare malignancy. According to the literature, primary malignancies of the female urethra, including CCAU, make up 0.003%–<1% of the genitourinary malignancies.^{12 13} Derksen et al¹⁴ analysed data from 91 females with primary urethral carcinoma registered in the National Cancer Registry of the Netherlands. The pathology analysis reveals CCAU in 6% of the cases.¹⁴ According to this study, the 5-year survival rate of adenocarcinoma of the urethra is 31%.⁹ Symptoms will vary and include a palpable tumour, urinary tract infections, irritating voiding symptoms, urethral pain, dyspareunia, obstructive voiding or haematuria.^13–15 There is no standard treatment for CCAU. However, the European Association of Urology (EAU) Guideline ‘Primary urethral carcinoma’ (2018, 4th edition) recommends different treatment options for women. Surgical intervention for localised urethral carcinoma can be urethrectomy or urethra-sparing surgery for anterior tumours.¹⁶ Local radiotherapy may also be considered as primary treatment but is associated with pelvic toxicity.¹⁶ The pathology report in this case is inconclusive as to the origin of the CCAU. Suggested is that the CCAU originates from the Müllerian or Wolffian remnants or Skene’s gland. In the literature, the origin of CCAU is debated; multiple hypotheses have been suggested. Several articles report CCAU originating from Skene’s gland, which is located in the centre of the urethral smooth muscle.^{13 15 17} Immunohistochemistry can have a positive prostate-specific antigen (PSA) staining, and in one case, elevated serum PSA is described.¹⁷ However, in our case, there was a negative PSA staining Reis et al showed that not all CCAU that originate from Skene’s gland are PSA positive with immunohistochemistry.¹⁵ Another hypothesis is that CCAU originates from either Müllerian remnants or urothelial metaplasia.^{18 19} Additionally, there is an association between clear cell adenocarcinoma and urethral diverticula, since 33%–50% of the CCAU develops in a urethral diverticula.¹⁸

As we have seen by discussing the three different cases, periurethral masses are uncommon and can prove to be a challenge to the medical professionals who treat them. Our research showed that the main challenge is the variety of symptoms and outcomes of the physical examination and the wide differential diagnosis with rare diseases. Whether a diagnosis must be made in all periurethral masses could be up for discussion. Blavais et al found that only in 2.5% of patients a malignant lesion was found; all the other patients had a benign lesion. Despite the small change that a periurethral mass is malignant, we would still recommend medical professionals to always further investigate a periurethral mass. The reason is that malignant lesions need aggressive therapy. In two of our case studies, the accurate diagnosis was established by MRI and confirmed with the pathology report. Only in the third case study the MRI did not provide a single diagnosis but a wide differential diagnosis. Therefore, we feel that pelvic MRI can be very useful and remains the method of choice for diagnosis. If there is a discussion whether surgical treatment must be performed, fine needle biopsy can be considered for histological characterisation of the mass. We advise to perform surgery in symptomatic patients or when the MRI indicates malignant characteristic.

Learning points.

• Periurethral masses are uncommon and provide a challenge to the medical professionals who treat them. Standard approach a periurethral mass with anamnesis, physical examination and cystoscopy.

• If an urethral diverticulum is considered as preliminary diagnosis, a voiding cystourethrogram can be performed. However, when a preliminary diagnosis cannot be made based on anamnesis, physical examination and cystoscopy, we advise to perform a pelvic MRI.

• The pelvic MRI is helpful to determine the borders of the mass, which is useful for future surgical treatment.