(August 2004) Introduction to Prostate Cancer The prostate is a small gland about the size and shape of a walnut situated just below the bladder and surrounding the urethra (the vessel that carries urine)(See Fig. 1). The prostate produces the seminal fluid in which sperm is transported. Figure 1. The Prostate Gland A cancer arises when cells stop growing in an organized and controlled manner. Without proper control cells grow rapidly, eventually forming a tumour. This is a common occurrence in the prostates of older men. Prostate cancer usually begins as a small focus, or several foci, of cancerous cells…