Prostate cancer is the most common non-skin cancer among American men. Public health records indicate that one in six American men will be faced with the diagnosis of prostate cancer during their lifetime. On average, about 189,000 men are diagnosed with prostate cancer each year with about 32,000 cases being fatal.
Prostate-specific antigen (PSA) is a protein almost exclusively produced by the prostate. Initially approved by the Food and Drug Administration for the purpose of monitoring the status of prostate cancer in 1986, PSA has become an integral part of prostate cancer screening along with a digital rectal examination (DRE). Men with prostate cancer often have elevated levels of serum PSA which correlate with the extent of cancer spread. With the introduction of PSA screening in the late 1980s, there has been a dramatic rise in the number of men diagnosed with localized prostate cancer; approximately 80 percent of newly diagnosed men are considered to have a clinically organ-confined disease that is potentially amenable to cure.
Once diagnosed, men with localized prostate cancer face a difficulty choosing amongst various treatment options. Several factors come into play when selecting an appropriate therapy. The stage (extent of local spread) and grade (aggressiveness) of prostate cancer, as well as competing medical co-morbidities and age at diagnosis, can all influence the decision regarding the choice of therapeutic intervention.
What are the current treatment options for men with localized prostate cancer?
Surgery (Radical Prostatectomy)
Surgery remains the primary option for many men with localized prostate cancer. Compared to other treatment methods such as radiotherapy and cryotherapy, a radical prostatectomy has an advantage of providing accurate local staging as well as assessment of pelvic lymph nodes through a detailed pathologic analysis. For patients with prostate cancer pathologically confined to the prostate, the chance of cure with surgery alone at 10 years (undetectable PSA) is more than 90 percent. The risk of cancer progression in men with extracapsular disease (cancer beyond the capsule of the prostate gland) and/or positive surgical margins is much higher ranging from 30 to 50 percent, and these patients may benefit from additional therapy such as external radiotherapy or androgen ablation. Although the incidence of surgical complications is quite low, the main postoperative issues remain urinary incontinence (5 percent) and erectile dysfunction (20 to 50 percent).
Open Radical Prostatectomy: In radical prostatectomy, the entire prostate gland is removed as a unit with the seminal vesicles and the nearest portions of the vas deferens. There are several different surgical techniques in performing a radical prostatectomy. The retropubic approach utilizes a midline incision below the umbilicus and allows simultaneous access to the prostate and pelvic lymph nodes. Based on precise anatomical delineation, the prostate gland can be safely removed with limited blood loss and preservation of the neurovascular bundles, which are responsible for maintaining erectile function. With the surgical steps clearly defined, the retropubic approach remains the most popular technique used by practicing urologists.
In perineal approach, the prostate is removed through a small semi-lunar incision in the perineum. By avoiding the pelvic vein complex, which can lead to significant bleeding in the retropubic approach, bleeding is usually minimal. Other advantages include precise urethra-vesical anastomosis (re-attaching the urethra to the bladder), a smaller incision, a shorter hospital stay and faster overall recovery. The main disadvantages are a higher incidence of rectal injury, difficulty of preserving the neurovascular bundles and a separate incision for pelvic lymphadenectomy. Typically, the perineal approach is preferred in obese individuals or those with prior lower abdominal surgery.
Robotic Assisted Laparoscopic Radical Prostatectomy: With recent advances in minimally invasive surgery and computer technology, the prostate gland can now be removed through a small one- to two-inch incision in the patient's abdomen. Introduced in 2001, robotic prostatectomy utilizes a surgical robotic system—named the da Vinci Robot (Intuitive Surgical, Inc., Sunnyvale, CA)—to remove the prostate gland through laparoscopic access in which surgeons make keyhole openings rather than a single 6 to 8-inch midline incision. The da Vinci Surgical System is the first surgical robotic system approved by the Food and Drug Administration for performing robotically assisted, minimally invasive surgery.
The system incorporates a surgeon's console and four interactive, robotic arms equipped with a camera and miniaturized surgical instruments. A surgeon controls the da Vinci's arms from a remote console that precisely translates his hand, wrist and finger movements to the robotic arms inside the patient's body while providing a three-dimensional view of those movements; the enhanced views offered by the da Vinci mean less chance of damaging surrounding nerves and tissue and a reduced risk of scarring. As a result, the incidence of postoperative erectile dysfunction and urinary incontinence appear to be much less than that of open radical prostatectomy. Furthermore, these small skin incisions result in less pain, less blood loss, faster catheter removal and a shorter hospital stay, with some patients returning to work as early as two weeks after the procedure. Patients who undergo this surgery generally leave the hospital the next day, and their overall recuperation time is reduced by half compared to that of standard open radical prostatectomy.
Despite its promising clinical results of robotic prostatectomy, the main caveat of this procedure is a steep learning curve in acquiring the surgical skills by the practicing urologists. It is estimated that the surgeon typically needs to perform 50 to 100 robotic prostatectomies before becoming facile with this approach.
Radiotherapy
Traditionally, radiotherapy has been reserved for an elderly population (over 70 years), men with locally advanced prostate cancer, and those with a short life expectancy (less than 15 years). Recent retrospective studies have shown that radiotherapy and surgery can offer comparable long-term outcomes up to 10 years, and as a result, the applicability of radiotherapy is no longer limited to the traditional indications. It is estimated that an equal number of patients undergo radical prostatectomy and radiotherapy at the present time.
Radiotherapy for prostate cancer can be divided into two modalities: external beam radiation (EBRT) and brachytherapy (PB). In external beam radiotherapy, a small amount of radiation is delivered incrementally to the prostate over a course of 6 to 7 weeks. The total radiation dose received is usually over 70 Gy. Currently, three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT) is used to deliver high-dose radiation to the prostate while minimizing toxicity to the surrounding normal structures such as the bladder and rectum.
Prostate brachytherapy is a method in which radioactive seeds are implanted directly into the prostate. The seeds are delivered percutaneously into the prostate via the specially designed needles under real time ultrasound imaging. Both low-dose rate (but high-dose) permanent prostate seeds and high dose rate (HDR) temporary implants can be used to treat the gland successfully. PB is typically performed in an outpatient setting under either general or regional anesthesia. The procedure is usually well tolerated with minimal perioperative morbidity.
The relative effectiveness of EBRT and PB appear to be similar for early stage prostate cancer. Some patients are offered the combination therapy in which both EBRT and PB are utilized. For those with locally advanced cancer and/or highly aggressive cancer, androgen deprivation is also added to optimize cancer control.
The main side effects of radiotherapy include bladder and rectal toxicities which can result in urinary and bowel dysfunction. The incidence of erectile dysfunction also appears to be similar to that of surgery, ranging in 20 to 50%. The long-term effects of radiation to normal tissues remain unknown though an incidence of secondary malignancy appears to be higher in this population.
Cryotherapy
Cryoablation of the prostate is a treatment in which prostate cancer is eradicated by freezing the prostate gland. Cryotherapy has a similar setup to that of prostate brachytherapy in that special needles called "cryoprobes" are placed into the prostate transperineally under the guidance of transrectal ultrasound. Argon gas is then used to create an "iceball" which results in instant cell death within the predefined area. Real time ultrasound monitoring of cryoablation combined with the use of thermocouples prevents cryo injuries to the surrounding normal tissues. Although prostate cryotherapy is most commonly offered after failed radiotherapy, there is emerging data supporting its use as a single treatment option in men with newly diagnosed prostate cancer. Cryotherapy currently has a limited role as an initial therapy in newly diagnosed men. In addition, cryotherapy should only be employed in men with erectile dysfuction as virtually all patients experience impotence following cryotherapy.
Androgen Ablation Therapy
Prostate cancer is androgen sensitive in early stages. As such, androgen ablation can result in a dramatic reduction in cancer burden in the vast majority of cases. Unfortunately, most prostate cancers eventually progress despite effective medical or surgical castration and become androgen independent. In the management of localized prostate cancer, the role of androgen ablation is usually limited to a neoadjuvant or adjuvant setting. Two most common scenarios are 1) to reduce the prostate size prior to prostate brachytherapy and 2) to sensitize malignant cells to radiation during EBRT. For patients who are at high risk for cancer recurrence, a prolonged use of androgen ablation (up to 3 years) combined with EBRT has resulted in improved survival compared to EBRT alone.
Watchful Wait or Expectant Management
Prostate cancer is often a slowly progressive disease, and many men with prostate cancer will die from causes other than prostate cancer. Several nomograms (decision charts) have been established in order to distinguish men with clinically significant cancers from those with clinically indolent tumors. In general, older men with a limited life expectancy and those with low-grade, small-volume disease may benefit from expectant management, and a therapeutic intervention should be reserved for those demonstrating clinical progression.
Reviewed November, 2006
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Glossary Terms
abdomen:
Also referred to as the belly. It is the part of the body that contains all of the internal structures between the chest and the pelvis.
ablation:
Removal of diseased or unwanted tissue from the body by surgery or other means.
adjuvant:
A drug or agent added to another drug or agent to enhance its medical effectiveness.
androgen:
Male sex hormone.
anesthesia:
Loss of sensation in any part of the body induced by a numbing or paralyzing agent. Often used during surgery to put a person to sleep.
bladder:
The balloon-shaped pouch of thin, flexible muscle in which urine is temporarily stored before being discharged through the urethra.
bowel:
Another word for intestines or colon.
brachytherapy:
Treatment for prostate cancer that involves the placement of tiny radioactive pellets into the prostate by utilizing ultrasound.
cancer:
An abnormal growth that can invade nearby structures and spread to other parts of the body and may be a threat to life.
catheter:
A thin tube that is inserted through the urethra into the bladder to allow urine to drain or for performance of a procedure or test, such as insertion of a substance during a bladder X-ray.
continence:
The ability to control the timing of urination or a bowel movement.
corpora:
Plural of corpus. The main portion of something, such as an organ or other body part, or a mass of tissue with a distinct function.
cryotherapy:
During an operation, probes are placed in the prostate. The probes are frozen thus killing the prostatic cells.
cutaneous:
Relating to the skin.
digital rectal examination:
Also known as DRE. Insertion of a gloved, lubricated finger into the rectum to feel the prostate and check for any abnormalities.
DRE:
Also known as digital rectal examination. Insertion of a gloved, lubricated finger into the rectum to feel the prostate and check for any abnormalities.
EBRT:
Also known as external beam radiation therapy. This technique involves directing a beam of radiation from outside the body focused on the cancerous internal organ and/or tissue within the body.
erectile:
Capable of filling with blood under pressure, swelling and becoming stiff.
erectile dysfunction:
Also known as ED or impotence. The inability to get or maintain an erection for satisfactory sexual intercourse. Also called impotence.
external beam radiation:
Radiation focused from a source outside the body on the affected area within the body.
gas:
Material that results from: swallowed air, air produced from certain foods or that is created when bacteria in the colon break down waste material. Gas that is released from the rectum is called flatulence.
gene:
The basic unit capable of transmitting characteristics from one generation to the next.
gland:
A mass of cells or an organ that removes substances from the bloodstream and excretes them or secretes them back into the blood with a specific physiological purpose.
impotence:
Also called erectile dysfunction or ED. The inability to get or maintain an erection for sexual activity.
incision:
Surgical cut for entering the body to perform an operation.
incontinence:
Loss of bladder or bowel control; the accidental loss of urine or feces.
invasive:
Having or showing a tendency to spread from the point of origin to adjacent tissue, as some cancers do. Involving cutting or puncturing the skin or inserting instruments into the body.
ions:
Electrically charged atoms.
laparoscopic:
Using an instrument in the shape of a tube that is inserted through the abdominal wall to give an examining doctor a view of the internal organs.
liver:
A large, vital organ that secretes bile, stores and filters blood, and takes part in many metabolic functions, for example, the conversion of sugars into glycogen. The liver is reddish-brown, multilobed, and in humans is located in the upper right part of the abdominal cavity.
lymph:
Fluid containing white cells. It can transport bacteria, viruses and cancer cells.
lymph nodes:
Small rounded masses of tissue distributed along the lymphatic system most prominently in the armpit, neck and groin areas. Lymph nodes produce special cells that help fight off foreign agents invading the body. Lymph nodes also act as traps for infectious agents.
lymphadenectomy:
Removal of adjacent lymph nodes.
malignancy:
A cancerous growth.
malignant:
A cancerous growth that is likely to grow and spread which can cause serious disablement or death.
pathologic:
Relating to disease or arising from disease.
pathological:
Relating to disease or arising from disease.
pelvic:
Relating to, involving or located in or near the pelvis.
percutaneous:
To place or perform a procedure underneath the skin. No incision (cutting) is necessary.
perineal:
Related to the area between the anus and the scrotum in males and the area between the anus and the vagina in females.
perineum:
The area between the anus and the scrotum in males and the area between the anus and the vagina in females.
probe:
Small device for measuring and testing.
prostate:
In men, a walnut-shaped gland that surrounds the urethra at the neck of the bladder. The prostate supplies fluid that goes into semen.
prostatectomy:
Surgical procedure for the partial or complete removal of the prostate.
PSA:
Also referred to as prostate-specific antigen. A protein made only by the prostate gland. High levels of PSA in the blood may be a sign of prostate cancer.
radiation:
Also referred to as radiotherapy. X-rays or radioactive substances used in treatment of cancer.
radical:
Complete removal.
radical prostatectomy:
Surgical removal of the prostate and seminal vesicles.
radioactive:
Relating to or making use of radioactive substances or the radiation they emit.
radiotherapy:
Also referred to as radiation therapy. High-energy rays are often used to damage cancer cells and stop them from growing and dividing.
rectal:
Relating to, involving or in the rectum.
rectal ultrasound:
A diagnostic test that uses very high frequency sound waves to produce an image of the rectum.
rectum:
The lower part of the large intestine, ending in the anal opening.
regional anesthesia:
Loss of sensation in the region of the body produced by application of an anesthetic agent to all nerves supplying that region.
seminal vesicle:
Two pouch-like glands behind the bladder. They produce a sugar-rich fluid called fructose that provides sperm with a source of energy that helps sperm move. The fluid of the seminal vesicles makes up most of the volume of a man's ejaculatory fluid, or ejaculate.
serum:
Clear, watery body fluid.
stage:
Classification of the progress of a disease.
tissue:
Group of cells in an organism that are similar in form and function.
toxicity:
Degree to which something is poisonous.
transrectal ultrasound:
Also referred to as TRUS. This is a special kind of ultrasound test in which the sound waves are produced by a probe inserted into the rectum. In men, the structures most commonly examined with this test are the prostate, bladder, seminal vesicles and ejaculatory ducts.
tumor:
An abnormal mass of tissue or growth of cells.
ultrasound:
Also referred to as a sonogram. A technique that bounces painless sound waves off organs to create an image of their structure to detect abnormalities.
umbilicus:
Navel or belly button.
urate:
A salt of uric acid.
urethra:
In males, this narrow tube carries urine from the bladder to the outside of the body and also serves as the channel through which semen is ejaculated. Extends from the bladder to the tip of the penis. In females, this short, narrow tube carries urine from the bladder to the outside of the body.
urge:
Strong desire to urinate.
urinary:
Relating to urine.
urinary incontinence:
Involuntary loss of urine associated with a sudden strong urge to urinate.
urinary incontinence:
Inability to control urination.
urinary incontinence:
Involuntary loss of urine associated with a sudden strong urge to urinate.
urinary incontinence:
Inability to control urination.
urologist:
A doctor who specializes in diseases of the male and female urinary systems and the male reproductive system. Click here to learn more about urologists. Click here to view the brochure in zinio format. (Download the free Zinio reader or the free Acrobat reader.)
vas:
Also referred to as vas deferens. The cordlike structure that carries sperm from the testicle to the urethra.
vas deferens:
Also referred to as vas. The cordlike structure that carries sperm from the testicle to the ejaculatory duct, whicn in turn carries it to the urethra.
vascular:
Having to do with blood vessels.
vein:
Blood vessel that drains blood away from an organ or tissue.
void:
To urinate, empty the bladder.
Article reproduced from the National Institute of Health and the National Library of Health. Government information at NLM Web sites is in the public domain. Public domain information may be freely distributed and copied. For more information visit www.nih.gov. The information contained in this article is not intended to provide advice on personal medical matters, nor is it intended to be a substitute for consultation with a medical professional.