When prostate cancer has metastasized, that means the cancer has spread beyond the prostate. Metastasis follows three ways: local invasion, intravasation and extravasation. Local invasion is where epithelial cells mix with stroma cells. The stroma cells make protein enzymes called proteases. Once local invasion has taken place, the cells enter into the bloodstream or lymphatic system. This process is called intravasation. After intravasation, the cells can escape to other parts of the body and continue to merge with healthy epithelial cells. This process is called extravasation.
Prostate Cancer is the most diagnosed cancer when causes and attributes to the second leading cause of death in males behind lung cancer. African American males have a higher rate of prostate cancer diagnosed and unfortunately a high mortality rate from prostate cancer.
The most common areas metastatic prostate cancer attacks is the bone structure. It has been reported that 95 percent of metastatic cancer invades the bones(mostly the spine, back and pelvis).
Because the cancer has spread to the bone, the treatment for this type of cancer is hormonal ablation therapy. By using hormonal ablation therapy, it can raise the 5 year survival rate to 20 to 30 percent.
Depending on the type of treatment used for prostate cancer, the rates of survival may be different. If the cancer was located in the prostate and near surrounding organs and the Gleason grade was around 6, the survival rate is 95% and does not matter if surgery or external beam radiation therapy was used.
The first doctor to test prostate cancer treatments on animals was Charles B. Huggins. Huggins used the anatomy of a dog to test the effects of phosphorus on the male reproductive system. By removal of the testes and reintroducing testosterone back into the system, cancer cells in the prostate gland decreased. Testosterone is a steroid responsible for the growth and development of the male reproductive system. This treatment has been referred to as “Hormone Ablation Therapy.” Hormone Ablation Therapy can be done by surgery or drug administration. Surgery involves removal of the testes to eliminate the production of testosterone. Huggins later concluded that removal of adrenal glands would eliminate further production of DHT (dihydrotestosterone). DHT was found to be a contributory in the production of prostate cancer cells.
Hormone Ablation Therapy by the use of drug administration involves 4 components: control of GnRH hormones, androgen receptor blockade, introduction of 5-alpha inhibitors and combined androgen blockage.
To control GnRh hormones, drugs that suppress prostate cancer cells are used to stop “luteinizing hormones” from the increase in the level of hormones in the body. The most common drug is DES(synthetic estrogen diethylstilbesterol).
With an androgen receptor blockage, drugs are introduced to stop the production of the testosterone and DHT from leaking to a healthy androgen cell. These drugs are referred to as “androgen receptor antagonists”.
When 5-alpha inhibitors are introduced into the system, these drugs work to reduce the amount of DHT in the body.
The use of combined androgen blockage involves drug therapy with the removal of the testes. This therapy is believed to attack the production of DHT and testosterone and reduce the growth of metastatic prostate cancer cells.
There are some side effects associated with hormone ablation therapy like erectile dysfunction and reduction in sex drive.
Hormone therapy to combat prostate cancer by interfering with testosterone can cause erectile dysfunction. Cryosurgery can cause erectile dysfunction because when the nerves in and surrounding the prostate are exposed to the cold temperatures, it can cause a loss in erectile function.