Objective    To study the diagnosis and treatment of small cell neuroendocrine carcinoma of the urinary bladder.     Methods    A retrospective study on pathological and clinical data of 4 cases of bladder small cell neuroendocrine carcinoma was made.      Results    The bladder small cell neuroendocrine carcinoma was diagnosed in 3 male patients and 1 female patient with mean age of 71 (63-83) years old. The staging was T

3

N

1

M

0

(1 case)

T

2

N

0

M

0

(2 cases) and T

3

N

0

M

0

(1 case). Two patients were treated with partial cystectomy

1 patient TUR-Bt

1 patient radical cystectomy. Of them 2 cases wer

e accompanied by transitional cell carcinoma or squamous carcinoma. All the 4 cases were followed-up for 11-35 months

3 patients died of the disease at average interval of 18 months (11

17

26 months respectively)

1 patient free of the disease for 35 months.      Conclusion    The bladder small cell neuroendocrine carcinoma is rare and highly malignant tumor. It is aggressive with early metastases and has a poor prognosis. Multi-drug combination chemotherapy combined with surgery appears to be the effective treatment.