Chromosomal imbalances in human bladder urothelial carcinoma: Similarities and differences between biopsy samples and cancer stem-like cells

The existence of two distinct groups of tumors with different clinical characteristic is a remarkable feature of transitional cell carcinomas (TCCs) of the bladder. More than 70% are low-grade (LG) non-infiltrating (NI) cancers at diagnosis, but 60-80% of them recur at least one time and 10-20% progress in stage and grade.