Cancer cell division. Coloured scanning electron micrograph (SEM) of two prostate cancer cells in the final stage of cell division (cytokinesis). During this stage the cells' cytoplasm divides. Here the cells are joined by a thin cytoplasmic bridge. Cancer cells divide rapidly in a chaotic, uncontrolled manner. They may clump to form tumours, which invade and destroy surrounding tissues. Prostate cancer affects the prostate gland of the male reproductive system, located below the bladder. It can cause difficulty in passing urine and an increased need to urinate. Magnification unknown.