Almost all prostate cancers are adenocarcinomas. These cancers develop from the gland cells (the cells that make the prostate fluid that is added to the semen).

Other types of cancer that can start in the prostate include:

• Small cell carcinomas
• Neuroendocrine tumors (other than small cell carcinomas)
• Transitional cell carcinomas
• Sarcomas

Except the adenocarcinoma, the other types of cancer are rare.