The prostate gland is located just below the bladder.
The prostate gland is a walnut-sized gland found in the male reproductive system that sits between the bladder and the rectum. When a diagnosis of prostate cancer is given, it means that cancer has been detected in prostate tissues. The disease may metastasize to surrounding anatomy, regional lymph nodes, and to organs within close proximity to the prostate, or to distant organs such as bones.
Prostate cancer rarely affects men under the age of 45. Seventy percent of prostate cancers occur in men over the age of 65. Studies show an increase in prostate cancer among African-American men when compared to other ethnicities; however, one in six men will eventually be diagnosed.
According to the American Cancer Society the most recent estimates (2011) predict that about 241,000 new cases of prostate cancer will be diagnosed.
There is evidence that suggests men may have a genetic predisposition to prostate cancer. Risks for developing prostate cancer include family history or a genetic mutation in genes BRCA1 and BRCA2. Individuals who are carriers of these genetic mutations are thought to have a two- to five-fold increase in risk for developing this disease. External risk factors associated with prostate cancer include diet, obesity, and prostate inflammation, as well as men who have been exposed to cadmium.
Symptoms associated with prostate cancer include the need to urinate frequently, difficulty in beginning urination, painful urination, or blood in the urine stream and/or semen.
Doctors will likely detect prostate cancer through a digital rectal exam (DRE) performed at an annual physical or a PSA blood test used to screen for the disease. A physician will then order a follow-up exam for confirmation of diagnosis, which will include a Computed Tomography (CT) scan, a core-needle biopsy of the suspected tumor, and in some cases a Magnetic Resonance Imaging (MRI) scan.
Treatment options for prostate cancer include surgery and various methods of radiation therapy, hormone treatment, and watchful waiting.
Surgical removal of the prostate gland is called a prostatectomy. While this option may be preferred by some, the risk for nerve damage is high given the close proximity of major nerve bundles in the pelvic region.
Radiation therapy is the use of accelerated particles or X-rays, which target cancerous cells to stop reproduction and growth of the tumor. Conventional radiation therapy (photons) is also known as external beam therapy. IMRT (Intensity Modulated Radiation Therapy), GammaKnife®, and CyberKnife ® are examples of conventional photon radiation therapy. Generally, treatment plans for conventional radiation therapy are designed with multiple treatment angles, which could increase dose to normal tissue.
Proton radiation therapy is another form of external beam radiation therapy. The IU Health Proton Therpay Center treats prostate cancer by delivering only two lateral treatment fields. An advance to proton therapy is that there is no exit dose past the tumor volume, which means less dose to normal tissue.
Brachytherapy is the use of radioactive seeds placed permanently within the prostate to irradiate cancerous cells. Small needles are inserted through the skin behind the scrotum in this kind of treatment. Brachytherapy may be given in conjunction with external beam radiation therapy treatments as well as hormone therapy.
Hormone therapy decreases the effect of testosterone on prostate cancer. It can prevent the spread of cancer and is mainly used to help relieve symptoms in men whose cancer has spread. Hormone therapy can be used in conjunction with another treatment such as proton therapy.
There are two types of drugs used for hormone therapy. The primary type blocks the body from making testosterone, and includes drugs like leuprolide, goserelin, nafarelin, triptorelin, histrelin, buserelin, and degarelix. The other medications used are called androgen-blocking drugs. They are often given along with the above hormone blockers. They include flutamide, bicalutamide, and nilutamide.
Potential side effects of prostatectomy include problems achieving or maintaining erections, urinary incontinence, damage to the urethra and/or rectum.
Side effects associated with radiation therapy include mild reddening of the skin, bowel issues (10% to 20%), impotence, fatigue, and lymphedema. Side effects are generally reduced or eliminated with proton therapy.
With hormone therapy, possible side effects include nausea and vomiting, hot flashes, anemia, lethargy, osteoporosis, reduced sexual desire, decreased muscle mass, weight gain, impotence liver problems, diarrhea, and enlarged breasts.
As is true with most malignant disease, the outcome for a patient with prostate cancer can be affected by many factors. It will differ greatly from individual to individual.
Upon diagnosis, biopsy results are reported using a Gleason grade and a Gleason score. The Gleason grade measures how aggressive the prostate cancer is considered to be. The score is based on a scale of one to five, one being the least aggressive and five being the most aggressive.
It is possible to have two samples from the same prostate with different Gleason scores. Therefore, a Gleason grade is created by adding the two most predominant grades together (a scale of two through 10). The likelihood that the cancer has spread outside of the prostate increases as the Gleason score nears 10. A score of two through four is typical of a low-grade cancer, a score of five through seven is considered a middle-grade cancer and a score of eight through 10 is considered high-grade cancer. Most men diagnosed with prostate cancer will fall in the intermediate range. In most cases, the more aggressive the tumor, the poorer the prognosis. However, even in individuals for which a cure seems unlikely, a combination of radiation and hormone therapy can extend life for up to several years.