Treating Advanced Prostate Cancer
Standards of Care in Hormone Therapy continued...
Timing of Cancer Treatment
The disagreement is due to conflicting beliefs. One is that endocrine therapy should begin only after symptoms from the metastases, like bone pain, occur. The counter belief is that endocrine therapy should start before symptoms occur. Earlier treatment of prostate cancer is associated with a lower incidence of spinal cord compression, obstructive urinary problems, and skeletal fractures. However, survival is not different whether treatment is started early, or deferred.
The only exception to the above, is in lymph node-positive, post-prostatectomy patients, given androgen deprivation as an adjuvant immediately after surgery. In this situation, immediate therapy resulted in a significant improvement in progression free survival, prostate cancer specific survival, and overall survival.
Length of Cancer Treatment
The disagreement in this situation is between continuous androgen deprivation (endocrine therapy) and intermittent androgen deprivation.
In early 2012, it was discovered that intermittent androgen deprivation is equal in long-term survival to continuous androgen deprivation. A new paradigm of treatment, in which androgen deprivation was given for 8-9 months and then discontinued if the PSA normalized, was published. Re-treatment is recommended only when the PSA level becomes greater than 10 with monitoring every two months.
Combination vs. Single-Drug Therapy
There is also disagreement about whether using a combination of endocrine therapies or just a single anti-androgen drug works best to treat prostate cancer. The studies are inconclusive. However, patients who receive combination therapy are more likely to experience treatment-related side effects than patients receiving a single form of hormone therapy.
Surgery for Prostate Cancer
In some cases of advanced or recurrent prostate cancer, surgeons may remove the entire prostate gland in a surgery known as "salvage" prostatectomy. They usually do not perform the nerve-sparing form of prostatectomy. Often, surgeons will remove the pelvic lymph nodes at the same time.
Cyrosurgery (also called cryotherapy) may be used in cases of recurrent prostate cancer if the cancer has not spread beyond the prostate. Cryosurgery is the use of extreme cold to destroy cancer cells.
To reduce testosterone levels in the body, doctors may sometimes recommend removing the testicles, a surgery called orchiectomy. After this surgery, some men choose to get prosthetics (artificial body parts) that resemble the shape of testicles.
Doctors may also remove part of the prostate gland with one of two procedures, either a transurethral resection of the prostate (TURP) or a or transurethral incision of the prostate (TUIP). This relieves blockage caused by the prostate tumor, so urine can flow normally. This is a palliative measure, which means it is done to increase the patient's comfort level, not to treat the prostate cancer itself.
Emerging Therapies for Prostate Cancer
Researchers are pursuing several new ways to treat advanced prostate cancer. Vaccines that alter the body's immune system and use genetically modified viruses show the most promise. One vaccine technique works by manipulating blood cells from the patient's immune system and causing them to attack the prostate cancer.
Blood is drawn from the patient. From the blood sample, cells that are part of the immune system (called dendritic cells) are exposed to cells that make up prostate cancer. Then the blood cells are placed back in the body, with the hope that they will cause other immune system cells to attack the prostate cancer. In a more traditional type of vaccine, the patient is injected with a virus that contains PSA. When the body is exposed to the virus, it becomes sensitized to cells in the body that contain PSA and his immune system attacks them.
Immune or genetic therapy have the potential to deliver more targeted, less invasive treatments for advanced prostate cancer. This would result in fewer side effects and better control of the prostate cancer.