David Baxter PhD
Late Founder
Progress On Prostate Cancer
InteliHealth
June 02, 2006
The past two decades have seen a dramatic increase in prostate cancer rates, followed by an equally impressive decline. Yet even as the number of men diagnosed with prostate cancer rose, the death rate dropped. What's going on?
We don't know. Some experts believe that the decline in the number of people dying of prostate cancer is clear evidence that aggressive screening and treatment strategies are paying off. Other experts note that prostate cancer deaths have declined even in countries where prostate cancer screening and surgery are rare. In the United States, regions where prostate cancer screening is common have not experienced more of a decline in prostate cancer deaths than regions where screening is infrequent.
The mystery of why fewer men are dying of prostate cancer and whether screening should be performed routinely in all men remain subjects of heated debate and controversy. The only point of agreement is that the declining mortality is a good thing.
There's no simple way to prevent prostate cancer, although researchers are studying dietary factors that may influence the risk (see The Dietary-Prostate Connection). However, there may be things that men can do to reduce their risk of dying of prostate cancer.
Ways To Detect Prostate Cancer
At its earliest, most curable stage, prostate cancer produces no symptoms. That's why many experts encourage men to consider regular screening with a digital rectal exam (DRE) and a blood test for prostate-specific antigen (PSA) levels. For example, the American Cancer Society recommends that all men older than 50 discuss the possible benefits of annual screening. Men at higher risk of prostate cancer ? those with a family history of the disease, as well as African-American men ? should consider testing beginning at age 45. A positive result from a DRE or a PSA test usually warrants follow-up diagnostic tests.
DRE. In a time of high-tech diagnostic wonders, the DRE is an old-fashioned, hands-on test ? literally. The physician inserts a gloved and lubricated finger into the rectum to feel for abnormalities of the prostate gland, which sits under the bladder (where it helps produce seminal fluid). Uncomfortable but mercifully brief, the DRE can detect prostate nodules that may be cancerous. If the exam reveals nothing, it's still possible that a growth may be located on a part of the prostate that the doctor can't reach. This is why a PSA test is usually done in addition to the DRE.
PSA Blood Test. High levels of the enzyme known as prostate-specific antigen, or PSA, often indicate some kind of prostate trouble, although not necessarily cancer. It's called "prostate specific" and not "cancer specific" for good reason: An elevated PSA level can also signal a simple infection or benign enlarged prostate. Conversely, it's possible to have a low PSA level and still have cancer.
In general, a man in his 40s should have a PSA level below 2.5 (nanograms per milliliter), a man in his 50s should be under 3.5, and an older man, under 4.0. For men with low PSA levels, a consistent increase of more than 1.5 over two years may signal trouble. Again, that doesn't necessarily mean prostate cancer. As with other cancer screening tests such as mammography, a positive test result needs confirmation.
Transrectal Ultrasound. This is the same technology that produces images of babies in the womb. While ultrasound can't distinguish healthy cells from cancer cells, it can help direct a needle biopsy.
Biopsy. During a biopsy, a special needle is used to remove prostate tissue for study under a microscope. Unlike cancers that typically form distinct, solid tumors, prostate cancer often produces tumor cells interspersed among healthy cells. So if the biopsy needle goes in a little too deep (or not quite deep enough), it can miss cancerous cells at a higher (or lower) level.
For that reason, if other test results strongly suggest prostate cancer, a biopsy that comes up negative may need to be repeated. If the biopsy confirms a diagnosis of prostate cancer, tests such as a bone scan, computed tomography (CT) scan or magnetic resonance imaging (MRI) may be needed to help decide on the best treatment.
Treatment Options
Prostate cancer is most easily ? and successfully ? treated when it's still "localized," meaning it has not yet spread outside the gland. Because many prostate tumors grow slowly, the best treatment is sometimes no treatment at all. In fact, many more men die with the disease rather than from it. For younger men and men with fast-growing tumors, today's treatment options can extend lives. Improvements in technology and techniques have greatly reduced the risk of side effects.
Here are the four main strategies for dealing with prostate cancer:
Watchful Waiting. In the case of an older man (with a life expectancy of less than 10 years) who has a slow-growing tumor, it often makes the most sense to postpone cancer treatment and take a wait-and-see approach, while monitoring the condition closely. If the tumor continues to grow slowly, treatment ? and its possible side effects ? can often be avoided altogether. If tumor growth accelerates, however, radiation or hormone therapy can then be considered.
Radical Prostatectomy. Most experts believe that complete surgical removal of the prostate gland is the best way to eradicate a localized tumor. This option is usually recommended for younger, healthy men. A prime candidate would be a man in his 50s, who may otherwise be expected to live another 20 years or more. In the hands of an experienced surgeon, the risk of serious side effects ? namely, loss of bladder control and sexual function ? is relatively low. Of course, the skill of the surgeon isn't the only factor to influence the likelihood of side effects; age and overall health have a great impact as well.
Radiation Therapy. Less invasive than surgery, radiation is often the best option for older men, especially those who have other medical problems or who may not tolerate major surgery. It's also the preferred treatment when cancerous cells are suspected to have spread beyond the prostate gland into adjacent tissue. Incontinence is less of an issue than with surgery, but radiation may also affect sexual function and damage the rectum.
Brachytherapy. Brachytherapy, which involves the implantation of radioactive "seeds" into the prostate gland, appears to be an attractive treatment for men with smaller, less aggressive prostate tumors. This treatment causes less side effects than conventional (external beam) radiation therapy.
Hormone Therapy. Most prostate tumors require testosterone to grow, and drugs that lower testosterone levels will cause cancer to shrink. Surgery to remove the testicles (orchiectomy) will have the same effect. Hormone therapy cannot cure prostate cancer by itself but is often an effective treatment for controlling the disease. It may be combined with radiation therapy to increase the likelihood of cure or used to control cancer in men who cannot be treated with surgery or radiation.
Prevention
In addition to regular screening, there?s been interest in whether certain hormone treatments may actually prevent prostate cancer in men at risk of the disease. A class of drugs known as 5-alpha reductase inhibitors, which includes finasteride (Proscar) and dutasteride (Avodart), are known to block a form of testosterone that appears to trigger growth of prostate cells. A large study of finasteride found that the drug cut the overall rate of prostate cancer by 30 percent ? but also increased the likelihood of developing the most aggressive form of the disease.
On balance, most experts feel that these drugs may cause as much harm as they prevent. However, ongoing research will help us to understand whether and when hormone therapy, or other drugs, may be useful for men who want to lower their chance of developing prostate cancer.
InteliHealth
June 02, 2006
The past two decades have seen a dramatic increase in prostate cancer rates, followed by an equally impressive decline. Yet even as the number of men diagnosed with prostate cancer rose, the death rate dropped. What's going on?
We don't know. Some experts believe that the decline in the number of people dying of prostate cancer is clear evidence that aggressive screening and treatment strategies are paying off. Other experts note that prostate cancer deaths have declined even in countries where prostate cancer screening and surgery are rare. In the United States, regions where prostate cancer screening is common have not experienced more of a decline in prostate cancer deaths than regions where screening is infrequent.
The mystery of why fewer men are dying of prostate cancer and whether screening should be performed routinely in all men remain subjects of heated debate and controversy. The only point of agreement is that the declining mortality is a good thing.
There's no simple way to prevent prostate cancer, although researchers are studying dietary factors that may influence the risk (see The Dietary-Prostate Connection). However, there may be things that men can do to reduce their risk of dying of prostate cancer.
Ways To Detect Prostate Cancer
At its earliest, most curable stage, prostate cancer produces no symptoms. That's why many experts encourage men to consider regular screening with a digital rectal exam (DRE) and a blood test for prostate-specific antigen (PSA) levels. For example, the American Cancer Society recommends that all men older than 50 discuss the possible benefits of annual screening. Men at higher risk of prostate cancer ? those with a family history of the disease, as well as African-American men ? should consider testing beginning at age 45. A positive result from a DRE or a PSA test usually warrants follow-up diagnostic tests.
DRE. In a time of high-tech diagnostic wonders, the DRE is an old-fashioned, hands-on test ? literally. The physician inserts a gloved and lubricated finger into the rectum to feel for abnormalities of the prostate gland, which sits under the bladder (where it helps produce seminal fluid). Uncomfortable but mercifully brief, the DRE can detect prostate nodules that may be cancerous. If the exam reveals nothing, it's still possible that a growth may be located on a part of the prostate that the doctor can't reach. This is why a PSA test is usually done in addition to the DRE.
PSA Blood Test. High levels of the enzyme known as prostate-specific antigen, or PSA, often indicate some kind of prostate trouble, although not necessarily cancer. It's called "prostate specific" and not "cancer specific" for good reason: An elevated PSA level can also signal a simple infection or benign enlarged prostate. Conversely, it's possible to have a low PSA level and still have cancer.
In general, a man in his 40s should have a PSA level below 2.5 (nanograms per milliliter), a man in his 50s should be under 3.5, and an older man, under 4.0. For men with low PSA levels, a consistent increase of more than 1.5 over two years may signal trouble. Again, that doesn't necessarily mean prostate cancer. As with other cancer screening tests such as mammography, a positive test result needs confirmation.
Transrectal Ultrasound. This is the same technology that produces images of babies in the womb. While ultrasound can't distinguish healthy cells from cancer cells, it can help direct a needle biopsy.
Biopsy. During a biopsy, a special needle is used to remove prostate tissue for study under a microscope. Unlike cancers that typically form distinct, solid tumors, prostate cancer often produces tumor cells interspersed among healthy cells. So if the biopsy needle goes in a little too deep (or not quite deep enough), it can miss cancerous cells at a higher (or lower) level.
For that reason, if other test results strongly suggest prostate cancer, a biopsy that comes up negative may need to be repeated. If the biopsy confirms a diagnosis of prostate cancer, tests such as a bone scan, computed tomography (CT) scan or magnetic resonance imaging (MRI) may be needed to help decide on the best treatment.
Treatment Options
Prostate cancer is most easily ? and successfully ? treated when it's still "localized," meaning it has not yet spread outside the gland. Because many prostate tumors grow slowly, the best treatment is sometimes no treatment at all. In fact, many more men die with the disease rather than from it. For younger men and men with fast-growing tumors, today's treatment options can extend lives. Improvements in technology and techniques have greatly reduced the risk of side effects.
Here are the four main strategies for dealing with prostate cancer:
Watchful Waiting. In the case of an older man (with a life expectancy of less than 10 years) who has a slow-growing tumor, it often makes the most sense to postpone cancer treatment and take a wait-and-see approach, while monitoring the condition closely. If the tumor continues to grow slowly, treatment ? and its possible side effects ? can often be avoided altogether. If tumor growth accelerates, however, radiation or hormone therapy can then be considered.
Radical Prostatectomy. Most experts believe that complete surgical removal of the prostate gland is the best way to eradicate a localized tumor. This option is usually recommended for younger, healthy men. A prime candidate would be a man in his 50s, who may otherwise be expected to live another 20 years or more. In the hands of an experienced surgeon, the risk of serious side effects ? namely, loss of bladder control and sexual function ? is relatively low. Of course, the skill of the surgeon isn't the only factor to influence the likelihood of side effects; age and overall health have a great impact as well.
Radiation Therapy. Less invasive than surgery, radiation is often the best option for older men, especially those who have other medical problems or who may not tolerate major surgery. It's also the preferred treatment when cancerous cells are suspected to have spread beyond the prostate gland into adjacent tissue. Incontinence is less of an issue than with surgery, but radiation may also affect sexual function and damage the rectum.
Brachytherapy. Brachytherapy, which involves the implantation of radioactive "seeds" into the prostate gland, appears to be an attractive treatment for men with smaller, less aggressive prostate tumors. This treatment causes less side effects than conventional (external beam) radiation therapy.
Hormone Therapy. Most prostate tumors require testosterone to grow, and drugs that lower testosterone levels will cause cancer to shrink. Surgery to remove the testicles (orchiectomy) will have the same effect. Hormone therapy cannot cure prostate cancer by itself but is often an effective treatment for controlling the disease. It may be combined with radiation therapy to increase the likelihood of cure or used to control cancer in men who cannot be treated with surgery or radiation.
Prevention
In addition to regular screening, there?s been interest in whether certain hormone treatments may actually prevent prostate cancer in men at risk of the disease. A class of drugs known as 5-alpha reductase inhibitors, which includes finasteride (Proscar) and dutasteride (Avodart), are known to block a form of testosterone that appears to trigger growth of prostate cells. A large study of finasteride found that the drug cut the overall rate of prostate cancer by 30 percent ? but also increased the likelihood of developing the most aggressive form of the disease.
On balance, most experts feel that these drugs may cause as much harm as they prevent. However, ongoing research will help us to understand whether and when hormone therapy, or other drugs, may be useful for men who want to lower their chance of developing prostate cancer.
