Searching For A Better Way To Diagnose Prostate Cancer
By Marge Dwyer
Beth Israel Deaconess Medical Center Correspondent
A Boston man in his 60s was anxious and confused when his doctor reported that a prostate-specific antigen (PSA) blood test showed he had early stage prostate cancer. He had read recent media reports about the shortcomings of this popular prostate screening test. He knew PSA tests weren’t always accurate— sometimes men had normal readings when they had cancer; other times the tests might indicate cancer when the men were healthy, resulting in unnecessary biopsies, treatments and perhaps unwelcome surgical side effects such as incontinence and impotence. Was the cancer fast-growing requiring swift treatment, or a slow growing cancer that might never become a problem in his lifetime?
No matter the shortcomings of the popular PSA test, Dr. Martin G. Sanda, Director of the Prostate Cancer Care Center in the Division of Urology at Boston’s Beth Israel Deaconess Medical Center, and other health professionals agree that the PSA blood test still is a valuable tool that has contributed to the nation’s declining death rate from prostate cancer in the last few years.
Instead of discarding PSA testing, Dr. Sanda and his colleagues are researching new ways to improve screening to better assess the health of the prostate gland, a walnut-size gland located near the bladder and in front of the rectum in men. The gland, which produces some of the semen that protects sperm, grows throughout a male’s life. By age 50 almost half of all men have elevated readings, meaning that they may be at increased risk for prostate cancer.
“Instead of throwing PSA testing in the garbage altogether, we are seeking to learn how we can improve prostate cancer screening,” Dr. Sanda says. “PSA tests do have a role but rather than giving every man with an abnormal reading a biopsy, we are trying to improve PSA testing and use it more selectively to determine who should have a biopsy.”
The American Cancer Society estimates that 192,280 men will be diagnosed with prostate cancer in 2009 and 27,360 will die from it, making it the second most deadly cancer among men in the nation, second to lung cancer. Prostate cancer is the most common type of cancer found in American men, other than skin cancer. One in six men will get prostate cancer during his lifetime, and one in 35 will die of the disease. That number is expected to increase in the future as life expectancy increases. More than 2 million American men who have had prostate cancer are living with the disease.
Two studies add to the confusion: the widely reported but inconclusive results of two large clinical studies evaluating the effectiveness of PSA testing earlier this year have raised more questions about the need to screen all men with the PSA test. The North American Prostate, Lung, Colon, and Ovarian Cancer Screening Trial (PLCO) study, which assigned patients randomly to undergo prostate screening by PSA tests and digital rectal exam, found no clear difference between the two groups studied. The larger European Randomized Study Screening for Prostate trial did show a significant reduction in prostate cancer deaths among men who had PSA testing. After nine years' follow-up, 326 prostate cancer deaths occurred in the control group vs. 214 in the group that underwent PSA testing once every four years.
“Many don’t know that the PLCO study was flawed,” Dr. Sanda says. At least 52 percent in the group who had agreed not to take a PSA test during the study ended up having the test. “So it’s not surprising that the results of the two groups in that study were about the same.”
Another question raised by the studies was the cost-effectiveness of testing all men with the PSA test. One study found that prostate-cancer screening saves less than one life per 1,000 people screened, which raised questions about how PSA might be used more efficiently.
Can new screening tools help?
Dr. Sanda and his colleagues are evaluating whether a checklist of risk factors can be paired with PSA results to decide which men should undergo a biopsy. These include:
“Our preliminary findings, reported at a meeting of the Early Detection Research Network of the National Cancer Institute in August 2009, show that the gene fusion can be detected in urine, and when it’s detected, this gene fusion predicts that biopsy will show prostate cancer,” Dr. Sanda says. “We hope to expand our studies to include more patients in the near future.”
In short, Dr. Sanda says, “You can act like an ostrich and put your head in the sand, pretend prostate cancer doesn’t exist and not do a PSA test. However, at BIDMC and other medical centers we take the attitude that to pretend prostate cancer doesn’t exist and to not do PSA testing is throwing the baby out with the bath water. The PSA test still is a valuable tool in determining who’s at risk for prostate cancer but that can be improved by incorporating recent research findings into urology clinical practice.”
Above content provided by Beth Israel Deaconess Medical Center. For advice about your medical care, consult your doctor.
Posted September 2009
Beth Israel Deaconess Medical Center Correspondent
A Boston man in his 60s was anxious and confused when his doctor reported that a prostate-specific antigen (PSA) blood test showed he had early stage prostate cancer. He had read recent media reports about the shortcomings of this popular prostate screening test. He knew PSA tests weren’t always accurate— sometimes men had normal readings when they had cancer; other times the tests might indicate cancer when the men were healthy, resulting in unnecessary biopsies, treatments and perhaps unwelcome surgical side effects such as incontinence and impotence. Was the cancer fast-growing requiring swift treatment, or a slow growing cancer that might never become a problem in his lifetime?
No matter the shortcomings of the popular PSA test, Dr. Martin G. Sanda, Director of the Prostate Cancer Care Center in the Division of Urology at Boston’s Beth Israel Deaconess Medical Center, and other health professionals agree that the PSA blood test still is a valuable tool that has contributed to the nation’s declining death rate from prostate cancer in the last few years.
Instead of discarding PSA testing, Dr. Sanda and his colleagues are researching new ways to improve screening to better assess the health of the prostate gland, a walnut-size gland located near the bladder and in front of the rectum in men. The gland, which produces some of the semen that protects sperm, grows throughout a male’s life. By age 50 almost half of all men have elevated readings, meaning that they may be at increased risk for prostate cancer.
“Instead of throwing PSA testing in the garbage altogether, we are seeking to learn how we can improve prostate cancer screening,” Dr. Sanda says. “PSA tests do have a role but rather than giving every man with an abnormal reading a biopsy, we are trying to improve PSA testing and use it more selectively to determine who should have a biopsy.”
The American Cancer Society estimates that 192,280 men will be diagnosed with prostate cancer in 2009 and 27,360 will die from it, making it the second most deadly cancer among men in the nation, second to lung cancer. Prostate cancer is the most common type of cancer found in American men, other than skin cancer. One in six men will get prostate cancer during his lifetime, and one in 35 will die of the disease. That number is expected to increase in the future as life expectancy increases. More than 2 million American men who have had prostate cancer are living with the disease.
Two studies add to the confusion: the widely reported but inconclusive results of two large clinical studies evaluating the effectiveness of PSA testing earlier this year have raised more questions about the need to screen all men with the PSA test. The North American Prostate, Lung, Colon, and Ovarian Cancer Screening Trial (PLCO) study, which assigned patients randomly to undergo prostate screening by PSA tests and digital rectal exam, found no clear difference between the two groups studied. The larger European Randomized Study Screening for Prostate trial did show a significant reduction in prostate cancer deaths among men who had PSA testing. After nine years' follow-up, 326 prostate cancer deaths occurred in the control group vs. 214 in the group that underwent PSA testing once every four years.
“Many don’t know that the PLCO study was flawed,” Dr. Sanda says. At least 52 percent in the group who had agreed not to take a PSA test during the study ended up having the test. “So it’s not surprising that the results of the two groups in that study were about the same.”
Another question raised by the studies was the cost-effectiveness of testing all men with the PSA test. One study found that prostate-cancer screening saves less than one life per 1,000 people screened, which raised questions about how PSA might be used more efficiently.
Can new screening tools help?
Dr. Sanda and his colleagues are evaluating whether a checklist of risk factors can be paired with PSA results to decide which men should undergo a biopsy. These include:
- The patient’s age and expected lifespan
- The patient’s weight. “Obesity is a huge risk factor for bad prostate cancer,” Sanda says.
- Family history: Is there cancer in the family?
- Size of the prostate: Men with larger prostates actually have a lower chance of having prostate cancer because their PSA can be high due to non-cancerous, “benign” enlargement of the prostate.
“Our preliminary findings, reported at a meeting of the Early Detection Research Network of the National Cancer Institute in August 2009, show that the gene fusion can be detected in urine, and when it’s detected, this gene fusion predicts that biopsy will show prostate cancer,” Dr. Sanda says. “We hope to expand our studies to include more patients in the near future.”
In short, Dr. Sanda says, “You can act like an ostrich and put your head in the sand, pretend prostate cancer doesn’t exist and not do a PSA test. However, at BIDMC and other medical centers we take the attitude that to pretend prostate cancer doesn’t exist and to not do PSA testing is throwing the baby out with the bath water. The PSA test still is a valuable tool in determining who’s at risk for prostate cancer but that can be improved by incorporating recent research findings into urology clinical practice.”
Above content provided by Beth Israel Deaconess Medical Center. For advice about your medical care, consult your doctor.
Posted September 2009
