[Mechanisms of tumour cell dissemination and methods for detection of circulating tumour cells in transitional cell carcinoma].

Systemic dissemination of single malignant cells from a tumour cell cluster represents an early essential step in the metastastic cascade of solid tumours. Studies in breast cancer and other solid malignancies have shown that the presence of circulating tumour cells (CTC) in the blood is associated with an unfavourable prognosis. In this article the key steps in the course of tumour cell dissemination and the basics of single cell detection are explained. The current literature about single cell detection in carcinoma of the breast and urothelial cancer is reviewed and the potential clinical implications of CTC-detection in bladder cancer are discussed. © Georg Thieme Verlag KG Stuttgart ˙ New York.