All types of cancer begin when cells unnecessarily grow and divide uncontrollably. In the case of prostate cancer, cells in the prostate gland begin to abnormally grow and increase in number, forming masses and tumors. The prostate gland, which is found only in males, is responsible for making some of the fluid in semen.
The prostate is located in front of the rectum and just below the bladder, and its size increases as a man gets older. The urethra – a thin tube that transports semen and urine out of the body via the penis – travels through the prostate’s center.
The vast majority of prostate cancers are adenocarcinomas, which develop directly from the prostate gland’s cells. Other, rare types of prostate cancer include: small cell carcinomas; sarcomas; transitional cell carcinomas and neuroendocrine tumors.