Lucia Gala Solana
Introduction Carcinoma arising in a bladder diverticulum is uncommon, and data on treatment and outcome are sparse. Our objective is to analyze clinicopathological features of diverticulum bladder cancer and difficulties on diagnosis. Clinical findings A 61-year old man healthy, never smoked, presented with frank hematuria and relapsing urinary lower tract infections with positive urine cultures to E. Coli. The clinic started a few months ago. Diagnosis and treatment Uroflowmetry was obstructive and urinary ultrasound revealed a small prostate with a large bladder diverticulum and a single stone within the diverticulum. Patient underwent cystoscopy under anesthesia. A large diverticulum on the right lateral wall was identified, without a real lithiasis, but a single calcified bladder tumour inside diverticulum. Neoplasm transurethral resection was incompletely performed because of obturator kicking and an elevated uncontrolled bleeding risk due to highly vascularized tumour bed. Pathology report revealed a high grade papillary urothelial carcinoma with extensively squamous differentiation with no muscularis propria or muscle staged as cT1R2. Random bladder biopsies and prostatic urethral biopsy were both negative. A multiphasic computed tomography scan showed a large diverticulum with narrow diverticular neck and residual tumour (2*3 cm) with doubt of perivesical tissues infiltration or inflammation post resection. No enlarged lymph nodes or other metastasis were detected (Fig. 1). Figure 1. Large diverticulum with residual tumour on CT scan. After discussing the treatment plan with the patient and his family and, with the difficulty to reliably predict tumour stage, a decision to do a laparoscopic radical cystectomy with standard lymph node dissection and orthotopic neobladder substitution was made. The pathology revealed a high-grade urothelial carcinoma with squamous differentiation with microscopically perivesical tissue infiltration and negative lymph nodes (on 29/29 identified lymph nodes) staged as pT3aN0. After 6 months, patient was free of tumour recurrence and recovered completely daytime continence in 3 months. Conclusions Neoplasms of urinary bladder diverticulum are uncommon, but not rare. Most malignant tumours in bladder diverticulum are transitional type, followed by squamous cell carcinoma. Bladder tumours arising in a diverticulum are difficult to diagnose because filling defects are not always visualized or they can be confused with stones due to calcified tumours. Bladder diverticulum neoplasms are characterized by early transmural invasion due to lack of muscular fibers thus, prompt diagnosis and treatment are crucial. Complete transurethral resection of diverticulum bladder tumours is often difficult considering the risk of bladder bleeding or perforation. Preoperative local staging remains a diagnostic challenge.