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The prostate is a part of the male reproductive system. The prostate is located just below the bladder and in front of the rectum. It is about the size of a walnut and surrounds the urethra (the tube that empties urine from the bladder). It produces fluid that makes up a part of semen.
As a man ages, the prostate tends to increase in size. This can cause the urethra to narrow and decrease urine flow. This is called benign prostatic hyperplasia, and it is not the same as prostate cancer.
Prostate cancer is a malignant tumour that starts in cells of the prostate. It can spread, or metastasize, to other parts of the body. Prostate cancer is the most common cancer in men. It usually grows slowly and can often be completely removed or managed successfully.
Risk factors:
Research has found risk factors that increase your chances of getting prostate cancer. These risk factors include:
· Age: The older a man is, the greater his risk for getting prostate cancer.
· Family history: Certain genes (the functional and physical units of heredity passed from parent to offspring) that you inherited from your parents may affect your prostate cancer risk. Currently, no single gene is sure to raise or lower your risk of getting prostate cancer. However, a man with a father, brother, or son who has had prostate cancer is two to three times more likely to develop the disease himself.
· Race: Prostate cancer is more common in some racial and ethnic groups than in others, but medical experts do not know why.
Symptoms:
Different people have different symptoms for prostate cancer. Some men do not have symptoms at all.
Some symptoms of prostate cancer are:
· Difficulty starting urination.
· Weak or interrupted flow of urine.
· Frequent urination, especially at night.
· Difficulty emptying the bladder completely.
· Pain or burning during urination.
· Blood in the urine or semen.
· Pain in the back, hips, or pelvis that doesn’t go away.
· Painful ejaculation.
Diagnosis:
If you or someone you care about has recently been diagnosed with prostate cancer, this section will help guide you through the complexities of this diagnosis and other issues to consider.
Understanding Your Diagnosis
A doctor typically diagnoses prostate cancer after closely examining biopsy cells through a microscope. There are several types of cells in the prostate, and each contributes in its own way to the prostate’s development, architecture, and function.
But cancer cells look different than normal prostate cells. Pathologists look for these differences first to detect the presence of cancer and then to determine the cancer grade.
Gleason Grading
The Gleason grading system accounts for the five distinct patterns that prostate tumor cells tend to go through as they change from normal cells to tumor cells.
The cells are scored on a scale from 1 to 5:
· “Low-grade” tumor cells (those closest to 1) tend to look very similar to normal cells.
· “High-grade” tumor cells (closest to 5) have mutated so much that they often barely resemble the normal cells.
The Gleason Score
The pathologist looking at the biopsy sample assigns one Gleason grade to the most predominant pattern in your biopsy and a second Gleason grade to the second most predominant pattern. The two grades added together determine your Gleason score (between 2 and 10).
Generally speaking, cancers with lower Gleason scores (2 – 4) tend to be less aggressive, while cancers with higher Gleason scores (7 – 10) tend to be more aggressive.
It’s also important to know whether any Gleason 5 is present, even in just a small amount, and most pathologists will report this. Having any Gleason 5 in your biopsy or prostate puts you at a higher risk of recurrence.
Diagnosing prostate cancer:
Diagnosis is the process of finding the underlying cause of a health problem. If cancer is suspected, the healthcare team will confirm if it is present or not, and what type of cancer it is. The process of diagnosis may seem long and frustrating, but it is important for the doctor to rule out other possible reasons for a health problem before making a cancer diagnosis.
Diagnostic tests for prostate cancer are usually done when:
- the symptoms of prostate cancer are present
- the doctor suspects prostate cancer after talking with a man about his health and completing a physical examination
- tests suggest a problem with the prostate
Many of the same tests used to initially diagnose cancer are also used to determine the stage (how far the cancer has progressed). Your doctor may also order other tests to check your general health and to help plan your treatment. Tests may include the following.
Medical history and physical examination
The medical history is a record of present symptoms, risk factors and all the medical events and problems a person has had in the past. The medical history of a man's family may also help the doctor to diagnose prostate cancer.
In taking a medical history, the doctor will ask questions about:
- a family history of prostate cancer or other cancers
- signs and symptoms, such as any changes in bladder habits
A physical examination allows the doctor to look for any signs of prostate cancer. During a physical examination, the doctor will do a digital rectal examination (DRE)
Prostate-specific antigen (PSA) test
A prostate-specific antigen (PSA) test is done to measure the level of PSA in the blood. PSA is a tumour marker. PSA is a protein made by the prostate. When it is present in the blood in abnormal amounts, it may indicate the presence of prostate cancer.
- The PSA level can be increased in men with prostate cancer, but it can also be increased in men with non-cancerous conditions such as an enlarged prostate (benign prostatic hyperplasia), or infection or inflammation.
- The PSA level varies with age and tends to rise gradually in older men.
- The higher the PSA level, the more likely that prostate cancer is present.
- Because PSA is a tumour marker, the PSA test is also used to check a man's response to prostate cancer treatment.
Transrectal ultrasound (TRUS)
Ultrasound uses high-frequency sound waves to make images of structures in the body. A transrectal ultrasound (TRUS) uses an ultrasound probe placed into the rectum to make images of the prostate. It is used to:
- measure the size of prostate
- look for abnormal or suspicious areas
- direct the placement of biopsy needles so that samples of tissue may be taken from the prostate
Biopsy
A biopsy is used to diagnose prostate cancer. A prostate biopsy may be done if an abnormality was found during a DRE or transrectal ultrasound. It may also be done if the PSA level was high for a man’s age or has increased over time or rapidly. It can be retrieved either transrectal ,transperineal or transurethral .
Blood chemistry tests
Blood chemistry tests measure certain chemicals in the blood. They show how well certain organs are functioning and can also be used to detect abnormalities. They are used to help stage prostate cancer.
- Blood urea nitrogen (BUN) and serum creatinine are measured to check kidney function. If these are higher than normal, it may mean that the prostate is blocking the ureters, the tubes that carry urine from the kidneys to the bladder.
- Increased alkaline phosphatase may indicate that prostate cancer has spread to the bone.
- Increased calcium may indicate that prostate cancer has spread to the bone.
Bone scan
A bone scan uses bone-seeking radioactive materials (radiopharmaceuticals) and a computer to create a picture of the bones. It is used to see if the prostate cancer has spread to the bones (the most common place where prostate cancer spreads).
Computed tomography (CT)
It is used to determine if the cancer has spread to the lymph nodes around the prostate gland. A CT scan is usually useful only for men diagnosed with prostate cancer who have a high PSA level (over 40) and a high Gleason score (over 7).
Magnetic resonance imaging (MRI)
MRI can sometimes show details that are not visible on a CT scan. An MRI may be used to see if prostate cancer has spread to the lymph nodes near the prostate or to surrounding tissues or structures.
Pelvic lymph node dissection
A pelvic lymph node dissection may be done to examine lymph nodes in the pelvis to see if the prostate cancer has spread. It may be done at the same time as surgery to remove the prostate (radical prostatectomy) or it may be done as a separate procedure in men who have a PSA level greater than 20 and a high Gleason score (8 or higher).
Treatment Options
There is no “one size fits all” treatment for prostate cancer. You should learn as much as possible about the many treatment options available and, in conjunction with your physicians, make a decision about what’s best for you. Because men diagnosed with localized prostate cancer today may live for many years, any decision made now will probably reverberate for a long time.
Your decision-making process will likely include a combination of clinical and psychological factors, including:
· The need for therapy
· Your level of risk
· Your personal circumstances
· Your desire for a certain therapy based on risks, benefits, and your intuition
Consultation with all three types of prostate cancer specialists—a urologist, a radiation oncologist, and a medical oncologist—will give you the most comprehensive assessment of the available treatments and expected outcomes.
Active surveillance:
The concept of active surveillance, or watchful waiting, has increasingly emerged in recent years as a viable option for men who decide not to undergo immediate surgery or radiation therapy.
During active surveillance, prostate cancer is carefully monitored for signs of progression. A PSA blood test and digital rectal exam (DRE) are usually administered periodically along with a repeat biopsy of the prostate at one year and then at specific intervals thereafter. If symptoms develop, or if tests indicate the cancer is growing, treatment might be warranted.
Prostatectomy (Surgery)
A surgical approach to treating prostate cancer will remove all or part of the prostate. Typically, men with early-stage disease or cancer that’s confined to the prostate will undergo radical prostatectomy—removal of the entire prostate gland, plus some surrounding tissue. Other surgical procedures may be performed on men with advanced or recurrent disease.
Radiation therapy:
radiation involves the killing of cancer cells and surrounding tissues with directed radioactive exposure. the use of radiation therapy as an initial treatment for prostate cancer is described below. some forms of radiation therapy can also be used in men with advanced or recurrent prostate cancer. it can be either achieved through external beam radiation therapy orbrachytherapy
Hormone Therapy
Prostate cancer cells are like other living organisms—they need fuel to grow and survive. Because the hormone testosterone serves as the main fuel for prostate cancer cell growth, it’s a common target for therapeutic intervention in men with the disease.
Hormone therapy, also known as androgen-deprivation therapy or ADT, is designed to stop testosterone from being released or to prevent it from acting on the prostate cells. Although hormone therapy plays an important role in men with advancing prostate cancer, it is increasingly being used before, during, or after local treatment as well.
The majority of cells in prostate cancer tumors respond to the removal of testosterone. But some cells grow independent of testosterone and remain unaffected by hormone therapy. As these hormone-independent cells continue to grow unchecked, hormone therapies have less and less of an effect on the growth of the tumor over time.
Chemotherapy
The term "chemotherapy" refers to any type of therapy that uses chemicals to kill or halt the growth of cancer cells. The drugs work in a variety of ways, but are all based on the same simple principle: stop the cells from dividing and you stop the growth and spread of the tumor.
Until recently, chemotherapy was used only to relieve symptoms associated with very advanced or metastatic disease. With the publication of two studies in 2004 showing that the use of docetaxel (Taxotere) can prolong the lives of men with prostate cancer that no longer responds to hormone therapy, more and more doctors are recognizing the potential benefits of chemotherapy for the men they treat with advanced prostate cancer.
Other Treatment Options
Targeted Therapies
Chemotherapy drugs can play an important role in improving the lives of men with advanced prostate cancer, but they often don’t distinguish between tumor cells and healthy cells to a high degree and can kill off some normal cells along the way. So-called targeted therapies, by contrast, are drugs that are specifically designed to interfere with the way cancer cells grow, with the way cancer cells interact with each other, and/or with the way that the immune system interact with the cancer without damaging a man’s normal cells.
There are a number of different kinds of targeted therapies being investigated for prostate cancer. As of yet, none have been approved by the FDA for use in prostate cancer, but the excitement generated by some of the early studies have led many researchers to believe that it’s only a matter of time before a targeted therapy is found that can result in better outcomes overall.
