The National Cancer Institute reports that more than 186,000 men in the United States are diagnosed with prostate cancer every year, and that it is the second most common cancer in American men. The prostate is a walnut-sized endocrine organ in men that lies between the rectum and bladder. The symptoms of prostate cancer include difficulty in urinating, pain and erectile dysfunction; however most men never develop symptoms. The American Cancer Society reports that approximately one man in 36 will die of prostate cancer and that five-year survival rate is almost 100 percent. Several types of prostate cancer exist.
Adenocarcinoma
The College of American Pathologists reports that more than 95 percent of prostate cancers are adenocarcinomas, relatively slow growing tumors that originate in the glandular tissue of the prostate. The Gleason grading system categorizes prostatic adenocarcinomas by size and location, architectural patterns and whether the cancer is confined to the prostate or has invaded other tissues.
Prostatic Sarcoma
Prostatic sarcomas account for less than 1 percent of prostate cancers. These tumors originate in muscle cells or connective tissue and may be referred to as rhabdomyosarcomas or leiyomyosarcomas. Unlike, prostatic adenocarcinomas, prostatic sarcomas have a poor prognosis. A study in the Journal of Urology reports that the one, three and five-year survival rates for patients with prostatic sarcoma are 81 percent, 43 percent and 38 percent, respectively.
Small Cell Carcinoma
Less than 1 percent of prostate cancers originate in the neuroendocrine cells of the prostate. A report in the Journal of the Royal Society of Medicine says in contrast to prostatic adenocarcinoma, small cell carcinoma of the prostate is aggressive and rapidly invades other organs and tissues including the bone, liver, lungs, lymph nodes and brain. This report also mentions that if left untreated, this type of prostatic cancer rapidly causes death. When it is detected, this cancer does respond to chemotherapy and radiotherapy.
