Introduction: Neuroendocrine carcinoma (NEC) of the bladder is a rare neoplasm representing fewer than 1% of all bladder tumors. Bladder NEC is frequently found in association with other histologic subtypes of bladder cancer and is usually treated with neoadjuvant chemotherapy followed by radical cystectomy. NEC of the bladder often has a poor prognosis, with quick relapse after surgery and short overall survival. 

Patient Information: We report the case of a 65yo man, with no relevant past medical history, who presented with acute gross hematuria in May 2018. Ultrasound documented a 4 cm solid lesion on the bladder wall, which was confirmed by a pelvic computed tomography (CT). CT showed no evidence of enlarged lymph nodes or distant metastases. A TURBT documented high-grade muscle invasive urothelial carcinoma (T2).

Treatment: Neoadjuvant chemotherapy with 4 cycles of cisplatin and gemcitabine was administered between August 2018 and October 2018, with good tolerance followed by a radical cystoprostatectomy with pelvic lymph node dissection and ileal conduit in November 2018. The pathological report documented a mixed urothelial and neuroendocrine carcinoma with invasion of the perivesical soft tissue, stage pT3N0 with Ki-67 of 75%. In February 2019, a follow-up CT documented disease relapse, with multiple lung micronodules, enlarged iliac lymph nodes and pelvic peritoneal implants compatible with metastases. A lymph node biopsy established the diagnosis of NEC metastasis (Ki-67 > 95%).

Follow-Up: Palliative chemotherapy with carboplatin and etoposide was started in April 2019. The CT performed after 4 cycles showed partial response, with almost complete disappearance of the pulmonary micronodules and pelvic peritoneal implants. To date, the patient is still undergoing chemotherapy, with good clinical tolerance. This case illustrates the aggressive course of bladder NEC, with short time to relapse after surgery with curative intent and negative resection margins.

A case of an unexpected neuroendocrine carcinoma of the bladder and its quick relapse after surgery