Diseases & Conditions

Prostate Cancer

Overview |
Symptoms |
Causes |
Risk Factors |
Diagnosis |
Treatment
Other Articles of Interest |
Providers |
Request an Appointment

Overview

Prostate cancer is the most common cancer in men and the second most common cause of cancer death in men. It is a slow growing cancer which is curable if detected early through digital rectal examinations or blood testing.

Symptoms

Prostate cancer initially causes no symptoms. As the tumor enlarges within the prostate, obstruction of the urine channel can result. This will result in a decreased strength of the urinary stream and more frequent urination. These same symptoms are most commonly seen in the non-cancerous enlargement of the prostate, benign prostatic hyperplasia.

Later, prostate cancer spreads to the lymph nodes and bones. Spread to the lymph nodes usually produces no symptoms. Bone metastases typically develop in the larger, marrow containing bones in the body. The spine, hips and pelvis are examples. Pain from metastases tends to be continuous and in the bone itself. Arthritic pain on the other hand is usually associated with physical activity and located in a joint or back.

[to top]

Causes

Prostate cancer is caused by a series of series of changes or mutations in the genes of prostate cells. These changes allow the cells to grow in an abnormal pattern until they form tumors. Later mutations allow the cells to escape the prostate and metastasize.

Risk Factors

Age
Prostate cancer is rare under the age of 40. The risk increases as one ages
Family history
Prostate cancer runs in families. Men with a father or brother with prostate cancer are at increased risk of developing the disease.
Ethnicity
African-Americans have the highest incidence of prostate cancer in the world. The disease incidence is also high in Scandinavian countries. Asians have low rates of prostate cancer. However, Asians living in the United States and practicing a Western lifestyle, have a prostate cancer incidence similar to other Americans.
Diet
Sun exposure
Studies suggest that prostate cancer is more common in areas with low sun exposure. Vitamin D is hypothesized to play a role in this risk.
Smoking

[to top]

Diagnosis

Prostate cancer is diagnosed through the combination of a digital rectal examination and a blood test to measure prostate specific antigen (PSA). PSA is an enzyme produced in large quantities by the prostate secretory glands. The function of this enzyme is to break down seminal proteins and convert semen from an initial gel form into a liquid. A small amount of PSA leaks out of the prostate and can be measured in the blood. The concentration of PSA in the semen is approximately a million times the level in the bloodstream. All men with a prostate produce PSA. PSA can be elevated by several conditions, including an enlarged prostate, infection or inflammation, trauma and recent sexual activity. An elevated PSA does not confirm the diagnosis of prostate cancer, Similarly, a low PSA does not rule out the presence of prostate cancer. The PSA test is used to assess cancer risk, and may prompt a prostate needle biopsy (link).

Modifications of the PSA test may improve cancer risk assessment. PSA velocity looks at the rate of PSA increase over several years. Men with more rapidly rising levels are more likely to have prostate cancer. Free PSA is enzymatically inactive PSA produced primarily by non-cancerous prostate tissue. A high percentage of free PSA is suggestive of an enlarged prostate, while a low free PSA fraction raises the concern for prostate cancer.

Prostate cancer screening with PSA and a digital rectal examination is recommended for men all men starting at age 50. For men with a family history of prostate cancer or African-Americans, screening should start at age 40. Screening should be discontinued at when the one’s expectancy is less than 10-15 years.

[to top]

Treatment

Localized Disease

There are a number of options for men with prostate cancer prostate cancer available. It is important to remember that all treatments are improved from 15-20 years ago. Comparisons between modern techniques and current techniques may not be valid. One of the most underutilized options is observation or watchful waiting. This option is appropriate for men with low volume disease or older men. Radiation therapy may be administered either as external beam radiotherapy (EBRT) or as brachytherapy (seed implants. Modern surgical techniques include nerve sparing radical prostatectomy and robotic assisted laparaoscopic radical prostatectomy.

Advanced disease

Hormone therapy
The prostate gland is a male sex gland and susceptible to hormonal manipulation. Prostate cancer cells retain this sensitivity to hormone manipulation. Cutting off the supply of the male hormone testosterone to the tumor cells will cause death of most, but not all prostate cancer cells. Typically, after a period of several years the prostate cells will lose their dependence on testosterone and begin to grow again in the absence of testosterone.

Hormone therapy can be performed in a variety of ways. An orchiectomy is an outpatient surgical procedure in which the testicles are removed. Estrogens (female hormones) may be administered to shut down testosterone production form the testicles. This treatment has fallen out of favor in recent years due to concerns of blood clot formation. More commonly, injections of LHRH agonists are administered at intervals ranging from monthly to yearly. These hormones signal the testicles decrease testosterone production.

Chemotherapy
In the past chemotherapy was not effective for the treatment of prostate cancer. Now, there are modern chemotherapy treatments which are effective in delaying disease progression. These treatments are usually administered by medical oncologists.

Clinical Trials

Through our multi-disciplinary clinic and in collaboration with the Seattle Cancer Care Alliance we offer numerous clinical trials for men with prostate cancer. These trials attempt to answer questions as to how best to treat prostate cancer. Some trials involve standard therapies. Other trials evaluate investigational treatments.

You may see a partial list of current clinical trial at the following links:

UWMedicine Research Studies seeking volunteers