Small cell cancer of the bladder: pathology, diagnosis, treatment and prognosis.

Small cell carcinoma of the bladder (SCCB) is rare, highly aggressive and diagnosed mainly at advanced stages. In addition, coexistence of SCCB with other types of carcinoma is common. Hematuria is the main symptom of this malignancy. Histological tests show a tumour, which is indistinguishable from small cell lung carcinoma (SCLC). Then immunohistochemistry tests may be helpful for a more precise diagnosis. Pathogenesis is uncertain; however the multipotent stem cell theory applies best to this case. The most common staging system used is the two-stage system (limited-extensive). Because of the rarity of the disease, the management is extrapolated from that of SCLC. Limited-stage disease should be treated with etoposide-cisplatin chemotherapy in combination either with radiotherapy, or surgery or both. Extensive-stage disease should be managed by combined chemotherapy. Further research programmes are needed to improve the diagnosis and the treatment of SCCB tumour. This paper would provide a comprehensive review of the epidemiology, clinical features, diagnosis, pathologic features, histogenesis, molecular genetics, staging, treatment, and prognosis of SCCB.