Revised: September 2006

General Information / Anatomy / Function / Statistics

• Gland found only in men
• Produces milky fluid that constitutes a significant portion of the ejaculate
• Located under the bladder and surrounds the urethra (tube that carries urine from the bladder to the exterior)
• Susceptible to a variety of conditions including benign enlargement after age of 40
• Cancer of prostate uncommon in younger men but overall it is the most common form of cancer among American and Canadian men
• May be slow growing, although behaviour varies
• For statistics, please see Statistics by Cancer Type

Symptoms / Signs

• Early stages - may be no symptoms
• Sometimes coincidentally detected after surgery for benign enlargement
• Hard lump - most commonly found in a routine physical examination (rectal exam)
• Enlargement of prostate may lead to difficulty in starting or stopping urination, slow stream, painful urination dribbling and/or frequent urination, loss of urinary control, blood in urine or ejaculate, nighttime voiding
• N.B. These symptoms are not specific to cancer but indicate a problem, which should be checked with a physician immediately

In advanced cases only:

• Weight loss
• Fatigue
• Backache or sciatica-like pain or swelling of the legs may be due to metastases

Etiology / Carcinogens / Risks

• The exact cause is unknown, related to the stimulatory action of testosterone (male sex hormone)
• The risk is twice as high in black men than in white men
• Men over 70 are at increased risk. It is very unusual under the age of 50
• Increases in incidence with age more rapidly than any other cancer
• The risk is proportional to the number of close relatives with prostate cancer
• Questions have been raised about a possible relationship between vasectomy and prostate cancer, but the evidence suggests this is coincidental not a causative factor
• The cancer has to be discovered before it spreads beyond the prostate gland to be curable

Prevention

Cancer researchers in Canada and else where are investigating the causes of prostate cancer. To date, none has been certainly identified. Researchers do suspect however that diet may be associated with the development of prostate cancer. Fats, especially those from animal sources, increase the risk of several cancers. On the other hand, foods such as green vegetables and fresh fruit may protect people against developing some cancers. The Canadian Cancer Society therefore urges men to adopt Canada's Guidelines for healthy eating (1991).

• Enjoy a variety of foods
• Emphasize cereals, breads and other grain products, vegetables and fruit
• Choose lower-fat dairy products, leaner meats and foods prepared with little or no fat
• Achieve and maintain a healthy body weight by enjoying regular physical activity and healthy eating

Information about the PSA Test and its use in Prostate Cancer from the BC Cancer Agency

By R. Gallagher, Genitourinary Tumour Group, BC Cancer Agency

The PSA test is a blood test that measures a substance produced by the prostate, called prostate specific antigen (PSA). There are 3 potential uses for PSA:

1. PSA may be used for monitoring established prostate cancer and metastatic disease (spread of prostate cancer) or detection of early recurrence of prostate cancer, where prostate cancer is already known
2. PSA may be used as a diagnostic adjunct in combination with other tests for early detection of prostate cancer in symptomatic men
3. As a screening tool

PSA testing is of unknown value as a population-screening test. Although there is good evidence that it increases the detection rate of early stage, clinically significant prostate cancers, there is little evidence to date that such early detection leads to reduced mortality; the "gold standard" for evaluating screening tests.

Fit men, aged 45-75 (men with at least 10 years life expectancy), should be made aware of the potential benefits and risks of early detection so that they can make an informed decision as to whether to have the test performed.

Additional Information about PSA:

• PSA levels of less than 4 are generally considered normal, however a prostate cancer may exist even though levels are normal. The upper limit of normal depends on age and race, so for example, the 'normal' for a 50 year old man is 2.5
• PSA levels higher than normal may indicate benign disease or prostate cancer. The higher the level, the more likely the presence of cancer. Refinements of the PSA test such as the percent free ratio, or the PSA velocity may increase its sensitivity for prostate cancer detection
• If a PSA level is elevated, further investigation and referral to a urologist is indicated
• If healthy men with no symptoms want a PSA test , they should speak to their family physician about the possible advantages and disadvantages of being tested. The cost is approximately $35.00. The PSA test may be covered by the medical plan if a physician has reason to suspect the patient may have cancer and feels the test is necessary due to suspicious symptoms
• Many prostate tumours can be felt with a rectal exam. However, small localized tumours are more likely to be detected by a combination of PSA and rectal exam

The BC Cancer Agency's Patient Information Document on PSA screening for prostate cancer is also available here.

Diagnosis / Staging / Grading / Types

Standard method of detection is as a result of digital rectal examination plus PSA test in a man with symptoms, or as a result of an abnormal screening PSA test.

Biopsy under ultrasound control:

• Ultrasound study of prostate should be accompanied by palpation biopsy
• Procedure: an ultrasound transducer is inserted into the rectum. Ultrasound may show abnormalities but not specific for cancer
• Ultrasound studies should be performed and interpreted by clinicians skilled in ultrasound procedures and with an excellent knowledge of prostate anatomy
• Transrectal ultrasound is the optimal method of biopsying the prostate, which can also be performed without the ultrasound test
• Needle biopsy
• Tumour grade (the Gleason score) is assigned to help predict the behavior of the cancer; higher grades are more likely to progress and spread

Metastatic check:

• Bone scan if PSA >10 (Prostate Specific Antigen) or high grade prostate cancer
• CT scan in some cases

Staging

• Based on examination and staging tests
  • T1 (A) Not palpable on rectal scan
  • T2 (B) A nodule that can be felt on rectal examination
  • T2a (B1) Small, on one side of the prostate only
  • T2b (B2) Both sides but confined to prostate
  • T3(C) Extends through the capsule of the prostate
  • T4 or N+(D-1) Prostate is fixed, or cancer has escaped to lymph nodes or beyond
  • M+(D2) Metastatic to other organs, e.g. bone

Types

• Adenocarcinomas account for 95% of cases. The following treatment section refers only to this type

Risk Grouping

• Using a combination of the Stage, pre-treatment PSA and Gleason Score, a risk group* can be given:
  • Low risk: stage T1c, T2a and PSA level <=10 ng/mL and Gleason score <=6
  • Intermediate risk: (neither high nor low risk) stage <= T2b and Gleason score of 7 and PSA level >10 and <=20 ng/mL
  • High risk: stage T2c or PSA level >20 ng/mL or Gleason score >=8

*adapted from: D'Amico AV, et al. JAMA. 1998;280:969-974.

Treatment

• Standard treatment includes surgery, radiation, hormone therapy or a combination. Some do not require active therapy (see also section 1). Type of treatment is influenced by the patient's age, medical condition and personal desires. For treatment options in localized prostate cancer, see below.
• What's a man to do? Treatment options for localized prostate cancer (Canadian Family Physician

Surgery

Pelvic Lymphadenectomy

• A procedure for lymph node sampling if the lymph nodes are positive for cancer, the prostate will usually not be removed. May be carried out by standard incision or via a laparoscopic approach

Transurethral Resection of Prostate (TUPR)

• There is no incision. A "resectoscope" is inserted through the penis and the layers of the prostate are removed with an electric wire loop. Each layer of dead cells is removed by a washing process and bleeding is controlled by electric current. A catheter may remain in place to help with urination. Used for treatment of benign prostate enlargement as a procedure that relieves obstruction and/or obtain tissue for diagnosis in the case of cancer

Radical Prostatectomy

• Used for localized cancer (stages T1-2)
• (Retropubic) prostatectomy: Incision is below the navel
• 1st step is to remove pelvic lymph nodes and if cancerous, the procedure ends (with some exceptions). If negative, the surgeon continues to remove the prostate
• All total prostatectomies remove the prostate gland and seminal vesicles
• Catheter is left in place for 10 to 21 days
• Pain is only moderate and controlled with medication
• A month's convalescence is required
• Males may lose their ability to have an erection after surgery but with recent surgical advances a proportion of patients retain their sexual function. This should be discussed with the surgeon
• Erections may be regained by using injection or vacuum device
• Ability to control urine may be impaired (incontinence)
• Incontinence is nearly always treatable by using external appliances, medication or surgical implants. Leaking often subsides after 6 to 12 months
• The usual risks of anaesthetics or pelvic surgery apply
• Surgery may be done through the perineum (Radical Perineal Prostatectomy)

Radiation

External Beam

• May be used for any stage of cancer. If the cancer is localized (T1-3) then the treatment is given with the intent of cure. More advanced cancers may be controlled with radiation
• Usually takes seven weeks
• Radiation treatment is delivered by high energy radiation
• May also be used to relieve symptoms caused by metastases, and single treatments may then be used
• May temporarily cause diarrhea and aggravation of hemorrhoids when used curatively to the prostate
• Survival rates for stage T1 and T2 cancer treated with radiation may be equivalent to those with prostatectomy, although no direct comparison has been done. Risk of recurrence is between 5-50%

Brachytherapy

• Involves implanting radioactive seeds directly into the prostate. For more information, see Brachytherapy Guidelines

Hormone Therapy

• Prostate cancers are mostly androgen (male hormone) dependent, so the manipulation of hormone levels in the body can relieve symptoms and reverse tumour growth
• The levels of male hormones can be decreased by removing the testes (orchiectomy), the glands which produce the hormones, or by the patient taking medication (medical castration)
• Medical or surgical castration (orchiectomy) results in impotence and loss of sex drive.
  Medical castration therapy with injections is equally effective
• Addition of anti-androgen tablets to medical or surgical castration adds side-effects and only a very minor additional benefit, and is not therefore usually recommended
• Hormone therapy may be added to radiation therapy to improve its effectiveness for localized cancer. Typically it is used for a few months before and a year or two after radiation
• Remissions with hormone therapy are temporary lasting, on average, two to three years, with occasional patients enjoying a long-term remission

Chemotherapy

• Used to relieve symptoms of advanced cancer but will not lead to a cure
• Chemotherapy (intravenous drug therapy) is being evaluated and can sometimes improve symptoms and provide temporary remissions in suitable patients
• Differentiating agents are currently under investigation

New Treatments

Cryosurgery

• Freezing of the prostate. It is still experimental

High Intensity Focused Ultrasound (HIFU)

• In response to a number of queries regarding the effectiveness of this therapy for the treatment of prostate cancer, the GU Tumour Group has carried out an evidence-based review (see the HIFU page in the BC Cancer Agency's Cancer Management Guidelines)