Primary squamous cell carcinoma of the urethral diverticulum mimicking prostate cancer: Case report and review of the literature

Abstract

Primary urethral carcinomas are uncommon, with urothelial carcinoma as the most common subtype. Urethral diverticulum is also rarely seen in men. A 44-year-old male presented with voiding symptoms. Abdominoperineal resection, prostatectomy, bladder neck excision, and proximal urethral excision were performed. A pathological examination revealed a well-differentiated squamous cell carcinoma (SCC) located inside an urethral diverticulum. We report this unusual case because primary SCC of the male urethral diverticulum is extremely rare. To our knowledge, our patient is only the second reported case. IntroductionPrimary urethral carcinoma (UC) is rare and accounts for less than 1% of all cancers.1,2 UC is the most common subtype. Generally, UCs are seen in the 5th decade.1,2 Patients presented with non-specific and overlapping clinical signs and symptoms.1,3 Management of UC is still controversial and challenging due to lack of experience.3 The surgical approach depends on the location and extent of the tumour. In advanced urethral squamous cell carcinoma (SCC), a combination of surgery, radiotherapy, and chemotherapy is recommended.3-6 The 5-year overall survival in patients with UC is about 50% to 55%. 2,3,5 Case reportA 44-year-old male presented with voiding difficulty and constipation for 3 months. He had a history of right nephrectomy for non-functional kidney secondary to a kidney stone. Although digital rectal examination revealed a hard, fixed mass on the anterior rectal wall, his prostate-specific antigen level was 0.61 ng/mL. A transrectal prostate biopsy was performed, and the pathological examination revealed a welldifferentiated SCC. The patient was referred to our urology clinic with a preliminary diagnosis of primary SCC of the prostate. A magnetic resonance imaging (MRI) showed a 6 × 7.2 × 8.1-cm round mass with smooth margins and heterogeneous internal enhancement. The mass abutted the rectum and bladder, and extended to the apex of the prostate and the levator ani without sign of invasion (Fig. 1). The prostate and lymph nodes were normal. For the purpose of a differential diagnosis, a colonoscopy was performed and the mucosa was normal. The patient underwent a cystourethroscopy and biopsy under anesthesia. We demonstrated a large wide-mouthed urethral diverticulum and tumour growth in the bulbomembranous urethral diverticulum. The prostate was normal and the dimensions of the prostate were compatible with the patient's age. The bladder mucosa was intact, with external tumour compression. A histopathologic examination revealed a well-differentiated SCC with an inverted and warty growth pattern, keratinization with keratin pearl and dyskeratotic cells.The patient was informed about the radical cystoprostatectomy and abdominoperineal resection if organ preservation was unfavourable, and informed consent was obtained. Abdominoperineal resection, prostatectomy, bladder neck excision, and proximal urethral excision were performed. On gross examination of the excision specimen, there was the pr...

Urethral diverticulum with stone formation in an adult male after hypospadias repair: A case presentation

“…While urethral diverticular carcinoma is extremely rare in men, a thorough examination, including the possibility of biopsies, is crucial for patients with calculi within the diverticulum. 9 , 10 …”