A Johns Hopkins study of 769 men from across the United States recently diagnosed with low-grade prostate cancer shows that forgoing immediate radiation or surgery to remove the tumor poses no added risk of death. Delaying treatment is fine, the results show, so long as the cancer’s progression and tumor growth are closely monitored through “active surveillance,” and there is no dramatic worsening of the disease over time.
None of the men, mostly 65 and older, have so far died from prostate cancer since the study began in 1995. However, one-third of study participants, monitored for as long as 15 years, eventually underwent treatment, primarily because annual biopsy results showed more cancer.
The study, to be published in the Journal of Clinical Oncology and posted online ahead of print, is believed to be the largest and longest study of men initially diagnosed with a slow-growing, very nonaggressive form of prostate cancer. This means they stand very little chance of dying from the disease, which was classified as very low risk, in its earliest stage, called T1c.
“This study offers the most conclusive evidence to date that active surveillance may be the preferred option for the vast majority of older men diagnosed with a very low-grade or small-volume form of prostate cancer,” said urologist H. Ballentine Carter, the study’s senior investigator. “These are men with a favorable risk disease profile to begin with.”
Carter, director of Adult Urology at The Johns Hopkins Hospital and a professor at the Johns Hopkins University School of Medicine and its Brady Urological Institute, acknowledged that “for some of these men, the prospect of living with prostate cancer is unbearable, and the tumor has to go.” But, he added, “the vast majority of these men are ideal candidates for active surveillance because they are older and are able to avoid the risks and complications associated with surgery and radiation.” The best candidates for surveillance programs, he said, are those who can be relied on to keep their medical appointments.
Some 217,000 men in the United States are diagnosed each year with prostate cancer, the majority of them older than 65 and with a low risk of dying from the disease if treatment is deferred, Carter said. Yet, more than 90 percent of these men with low-risk disease, including some 80 percent of those over 75, are likely to choose some form of treatment instead of surveillance.
“Our findings really underscore the need to address excessive treatment of this milder stage of the disease in older men, especially seniors,” Carter said.
Possible complications from surgery or radiation to treat tumors, he said, primarily include incontinence and other bowel, urinary or sexual problems.
Just as significantly, Carter and his team noted, the study highlights the importance of carefully selecting patients who are least likely to benefit from treatment.
The study showed that men who strictly met all study criteria for very low-risk disease were 30 percent less likely to be reclassified to a high-risk category during surveillance and to need subsequent surgery or radiation than men who did not meet one or more study criteria.
All study participants, 90 percent white and 6 percent black, met the key criteria of having a prostate cancer Gleason score of 6 or less. The score is used to rate the severity of the disease. Higher scores, typically from 7 through 10, suggest a more-aggressive form of the disease that in most cases would require treatment.
Eighty percent of men involved in the latest analysis met at least one or more other study criteria for small-volume tumors. These included the amount of cancer found on biopsy of the prostate gland plus a ratio of blood levels of a protein linked to the cancer, called prostate-specific antigen, to gland size, or PSA density. Fewer than three biopsy cores could have cancer, with the disease present in no more than half of any core. Most study participants had a PSA density of less than 15 percent.
Men were enrolled in the study from 1995 through 2010 and are being monitored through semiannual checkups and yearly biopsies.
Carter’s team plans to expand the surveillance study program to other medical centers, including Cedars-Sinai Medical Center in Los Angeles, to further refine the selection criteria.
Current guidelines endorsed by the National Comprehensive Cancer Network, he said, could be broadened as a result of the study and already list active surveillance as a preferred course of action for many older men, especially seniors.
The Johns Hopkins team and the Prostate Cancer Foundation, which helped fund the latest study, have plans to develop a Web-based educational program to directly promote active surveillance to men newly diagnosed with the disease. Another of the team’s goals, he said, is to develop better screening tests for identifying men best-suited to a surveillance program.
Additional funding support for the study was provided by the Patrick C. Walsh Prostate Cancer Research Fund.
Johns Hopkins investigators involved in this study, in addition to Carter, were lead investigator Jeffrey Tosoian, Bruce Trock, Patricia Landis, Zhaoyong Feng, Jonathan Epstein, Alan Partin and Patrick Walsh.
Article from http://gazette.jhu.edu/
The National Cancer Institute fact sheet about the PSA test is useful to better understand all aspects of the PSA test, including benefits and limitations.
- Prostate-specific antigen (PSA) is a protein produced by cells of the prostate gland. The PSA test measures the level of PSA in the blood (see Question 1).
- The U.S. Food and Drug Administration (FDA) has approved the use of the PSA test along with a digital rectal exam to help detect prostate cancer in men age 50 and older. The FDA has also approved the PSA test to monitor patients with a history of prostate cancer to see if the cancer has recurred (come back) (see Question 2).
- Doctors’ recommendations for PSA screening vary (see Question 3).
- The higher a man’s PSA level, the more likely it is that cancer is present, but there are other possible reasons for an elevated PSA level (see Questions 4 and 5).
- Doctors take several factors into account for men who have a rising PSA level after treatment for prostate cancer (see Questions 2 and 6).
- The PSA test for screening has limitations and is still controversial (see Questions 7 and 8).
- Researchers are studying ways to validate and improve the PSA test and to find other ways of detecting prostate cancer early (see Questions 9 and 10).
1. What is the prostate-specific antigen (PSA) test?
Prostate-specific antigen (PSA) is a protein produced by cells of the prostate gland. The PSA test measures the level of PSA in the blood. The doctor takes a blood sample, and the amount of PSA is measured in a laboratory. Because PSA is produced by the body and can be used to detect disease, it is sometimes called a biological marker or a tumor marker.
It is normal for men to have a low level of PSA in their blood; however, prostate cancer or benign (not cancerous) conditions can increase a man’s PSA level. As men age, both benign prostate conditions and prostate cancer become more common. The most frequent benign prostate conditions are prostatitis (inflammation of the prostate) and benign prostatic hyperplasia (BPH) (enlargement of the prostate). There is no evidence that prostatitis or BPH causes cancer, but it is possible for a man to have one or both of these conditions and to develop prostate cancer as well.
A man’s PSA level alone does not give doctors enough information to distinguish between benign prostate conditions and cancer. However, the doctor will take the result of the PSA test into account when deciding whether to check further for signs of prostate cancer.
2. Why is the PSA test performed?
The U.S. Food and Drug Administration (FDA) has approved the use of the PSA test along with a digital rectal exam (DRE) to help detect prostate cancer in men 50 years of age or older. During a DRE, a doctor inserts a gloved finger into the rectum and feels the prostate gland through the rectal wall to check for bumps or abnormal areas. Doctors often use the PSA test and DRE as prostate cancer screening tests; together, these tests can help doctors detect prostate cancer in men who have no symptoms of the disease.
The FDA has also approved the use of the PSA test to monitor patients who have a history of prostate cancer to see if the cancer has recurred (come back). If a man’s PSA level begins to rise, it may be the first sign of recurrence. Such a “biochemical relapse” typically precedes clinical signs and symptoms of a relapse by months or years. However, a single elevated PSA measurement in a patient with a history of prostate cancer does not always mean the cancer has come back. A man who has been treated for prostate cancer should discuss an elevated PSA level with his doctor. The doctor may recommend repeating the PSA test or performing other tests to check for evidence of a recurrence. The doctor may look for a trend of rising PSA measurements over time rather than a single elevated PSA level.
It is important to note that a man who is receiving hormone therapy for prostate cancer may have a low PSA level during, or immediately after, treatment. The low level may not be a true measure of the man’s PSA level. Men receiving hormone therapy should talk with their doctor, who may advise them to wait a few months after hormone treatment before having a PSA test.
3. For whom might a PSA screening test be recommended?
Doctors’ recommendations for screening vary. Some encourage yearly screening for men over age 50, and some advise men who are at a higher risk for prostate cancer to begin screening at age 40 or 45. Others caution against routine screening. Although specific recommendations regarding PSA screening vary, there is general agreement that men should be informed about the potential risks and benefits of PSA screening before being tested. Currently, Medicare provides coverage for an annual PSA test for all men age 50 and older.
Several risk factors increase a man’s chances of developing prostate cancer. These factors may be taken into consideration when a doctor recommends screening. Age is the most common risk factor, with nearly 63 percent of prostate cancer cases occurring in men age 65 and older (1). Other risk factors for prostate cancer include family history, race, and possibly diet. Men who have a father or brother with prostate cancer have a greater chance of developing prostate cancer. African American men have the highest rate of prostate cancer, while Asian and Native American men have the lowest rates. In addition, there is some evidence that a diet higher in fat, especially animal fat, may increase the risk of prostate cancer.
4. How are PSA test results reported?
PSA test results show the level of PSA detected in the blood. These results are usually reported as nanograms of PSA per milliliter (ng/mL) of blood. In the past, most doctors considered a PSA level below 4.0 ng/mL as normal. In one large study, however, prostate cancer was diagnosed in 15.2 percent of men with a PSA level at or below 4.0 ng/mL (2). Fifteen percent of these men, or approximately 2.3 percent overall, had high-grade cancers (2). In another study, 25 to 35 percent of men who had a PSA level between 4.1 and 9.9 ng/mL and who underwent a prostate biopsy were found to have prostate cancer, meaning that 65 to 75 percent of the remaining men did not have prostate cancer (3).
Thus, there is no specific normal or abnormal PSA level. In addition, various factors, such as inflammation (e.g., prostatitis), can cause a man’s PSA level to fluctuate. It is also common for PSA values to vary somewhat from laboratory to laboratory. Consequently, one abnormal PSA test result does not necessarily indicate the need for a prostate biopsy. In general, however, the higher a man’s PSA level, the more likely it is that cancer is present. Furthermore, if a man’s PSA level continues to rise over time, other tests may be needed.
Because PSA levels tend to increase with age, the use of age-specific PSA reference ranges has been suggested as a way of increasing the accuracy of PSA tests. However, age-specific reference ranges have not been generally favored because their use may lead to missing or delaying the detection of prostate cancer in as many as 20 percent of men in their 60s and 60 percent of men in their 70s. Another complicating factor is that studies to establish the normal range of PSA values have been conducted primarily in white men. Although expert opinions vary, there is no clear consensus on the optimal PSA threshold for recommending a prostate biopsy for men of any racial or ethnic group.
5. What if the screening test results show an elevated PSA level?
A man should discuss an elevated PSA test result with his doctor. There can be different reasons for an elevated PSA level, including prostate cancer, benign prostate enlargement, inflammation, infection, age, and race.
If no symptoms to suggest cancer are present, the doctor may recommend repeating DRE and PSA tests regularly to watch for any changes. If a man’s PSA level has been increasing or if a suspicious lump is detected during a DRE, the doctor may recommend other tests to determine if there is cancer or another problem in the prostate. A urine test may be used to detect a urinary tract infection or blood in the urine. The doctor may recommend imaging tests, such as a transrectal ultrasound (a test in which high-frequency sound waves are used to obtain images of the rectum and nearby structures, including the prostate), x-rays, or cystoscopy (a procedure in which a doctor looks into the urethra and the bladder through a thin, lighted tube that is inserted through the end of the penis; this can help determine whether urinary blockage is caused by an enlarged prostate). Medicine or surgery may be recommended if the problem is BPH or an infection.
If cancer is suspected, a biopsy is needed to determine whether cancer is present in the prostate. During a biopsy, samples of prostate tissue are removed, usually with a needle, and viewed under a microscope. The doctor may use ultrasound to view the prostate during the biopsy, but ultrasound cannot be used alone to tell if cancer is present.
6. What if the test results show a rising PSA level after treatment for prostate cancer?
A man should discuss rising PSA test results with his doctor. Doctors consider a number of factors before recommending further treatment. Additional treatment based on a single PSA test result is often not recommended. Rather, a rising trend in PSA test results over a period of time combined with other findings, such as an abnormal DRE, positive prostate biopsy results, or abnormal CT (computed tomography) scan results, may lead to a recommendation for further treatment.
According to the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology for Prostate Cancer (4), additional treatment may be indicated based on the following PSA test results:
- For men who have been in the watchful waiting phase—their PSA level has doubled in fewer than 3 years or they have a PSA velocity (change in PSA level over time) of greater than 0.75 ng/mL per year, or they have a prostate biopsy showing evidence of worsening cancer (4).
- For men who have had a radical prostatectomy (removal of the prostate gland)—their PSA level does not fall below the limits of detection after surgery or they have a detectable PSA level (> 0.3 ng/mL) that increases on two or more subsequent measurements after having no detectable PSA (4).
- For men who have had other initial therapy, such as radiation therapy with or without hormonal therapy—their PSA level has risen by 2 ng/mL or more after having no detectable PSA or a very low PSA level (4).
Please note that these are general guidelines. Prostate cancer is a complex disease and many variables need to be considered by each patient and his doctor.
7. What are some of the limitations of the PSA test?
- Detecting tumors does not always mean saving lives: When used in screening, the PSA test can detect small tumors. However, finding a small tumor does not necessarily reduce a man’s chances of dying from prostate cancer. PSA testing may identify very slow-growing tumors that are unlikely to threaten a man’s life. Also, PSA testing may not help a man with a fast-growing or aggressive cancer that has already spread to other parts of his body before being detected.
- False-positive tests: False-positive test results (also called false positives) occur when the PSA level is elevated but no cancer is actually present. False positives may lead to additional medical procedures that have potential risks and significant financial costs and can create anxiety for the patient and his family. Most men with an elevated PSA test result turn out not to have cancer; only 25 to 35 percent of men who have a biopsy due to an elevated PSA level actually have prostate cancer (3).
- False-negative tests: False-negative test results (also called false negatives) occur when the PSA level is in the normal range even though prostate cancer is actually present. Most prostate cancers are slow-growing and may exist for decades before they are large enough to cause symptoms. Subsequent PSA tests may indicate a problem before the disease progresses significantly.
8. Why is the PSA test controversial in screening?
Using the PSA test to screen men for prostate cancer is controversial because it is not yet known for certain whether this test actually saves lives. Moreover, it is not clear that the benefits of PSA screening outweigh the risks of follow-up diagnostic tests and cancer treatments. For example, the PSA test may detect small cancers that would never become life threatening. This situation, called overdiagnosis, puts men at risk of complications from unnecessary treatment.
The procedure used to diagnose prostate cancer (prostate biopsy) may cause harmful side effects, including bleeding and infection. Prostate cancer treatments, such as surgery and radiation therapy, may cause incontinence (inability to control urine flow), erectile dysfunction (erections inadequate for intercourse), and other complications. For these reasons, it is important that the benefits and risks of diagnostic procedures and treatment be taken into account when considering whether to undertake prostate cancer screening.
9. What research is being done to validate and improve the PSA test?
The benefits of screening for prostate cancer are still being studied. The National Cancer Institute (NCI), a component of the National Institutes of Health, is currently conducting the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, or PLCO trial, to determine whether certain screening tests can help reduce the number of deaths from these cancers. The PSA test and DRE are being evaluated to determine whether yearly screening to detect prostate cancer will decrease a man’s chances of dying from this disease.
Initial results from the trial showed that annual PSA testing for 6 years and annual DRE testing for 4 years (performed in the same years as the first four PSA tests) did not reduce the number of deaths from prostate cancer through a median follow-up period of 11.5 years (range 7.2 to 14.8 years) (5). At 7 years of follow-up, a point in time when follow-up of the participants was essentially complete, 23 percent more cancers had been diagnosed in the screening group than in the control group. In the control group, men were randomly assigned to “usual care.”
These results suggest that many men were diagnosed with, and treated for, cancers that would not have been detected in their lifetime without screening and, as a consequence, were exposed to the potential harms of unnecessary treatments, such as surgery and radiation therapy. Nevertheless, it remains possible that a small benefit from the earlier detection of these “excess” cancers could emerge with longer follow-up. Follow-up of the PLCO participants will continue, therefore, until all participants have been followed for at least 13 years.
In contrast, initial results from another large randomized, controlled trial of prostate cancer screening, called the European Randomized Study of Screening for Prostate Cancer (ERSPC), found a 20 percent reduction in prostate cancer deaths associated with PSA testing every 4 years (6). At the time the results were reported, the participants had been followed for a median of 9 years. The average number of PSA tests per participant in ERSPC was 2.1. Most participating centers in this study used a lower PSA cutoff value as an indicator of abnormality than was used in the PLCO trial (3.0 ng/mL versus 4.0 ng/mL). As in the PLCO trial, many more cancers were diagnosed in the screening group than in the control group. The ERSPC researchers estimated that 1,410 men would have to be screened and 48 additional cancers would have to be detected to prevent one death from prostate cancer (6).
Scientists are also researching ways to improve the PSA test, hopefully to allow cancerous and benign conditions, as well as slow-growing cancers and fast-growing, potentially lethal cancers, to be distinguished from one another. Some of the methods being studied include the following:
- PSA velocity: PSA velocity is the change in PSA level over time. A sharp rise in the PSA level raises the suspicion of cancer and may indicate a fast-growing cancer. A 2006 study found that men who had a PSA velocity above 0.35 ng/mL per year had a higher relative risk of dying from prostate cancer than men who had a PSA velocity less than 0.35 ng/mL per year (7). More studies are needed to determine if a high PSA velocity more accurately detects prostate cancer early.
- PSA density: PSA density considers the relationship between the level of PSA and the size of the prostate. In other words, an elevated PSA level might not arouse suspicion if a man has a very enlarged prostate. The use of PSA density to interpret PSA results is controversial because cancer might be overlooked in a man with an enlarged prostate.
- Free versus attached PSA: PSA circulates in the blood in two forms: Free or attached to a protein molecule. The free PSA test is more often used for men who have higher PSA values. Free PSA may help tell what kind of prostate problem a man has. With benign prostate conditions (such as BPH), there is more free PSA, while cancer produces more of the attached form. If a man’s attached PSA level is high but his free PSA level is not, the presence of cancer is more likely. In this case, more testing, such as a prostate biopsy, may be done. Researchers are exploring additional ways of measuring PSA and comparing these measurements to determine whether cancer is present.
- Alteration of PSA cutoff level: Some researchers have suggested lowering the cutoff levels used to determine whether a PSA measurement is normal or elevated. For example, a number of studies have used cutoff levels of 2.5 or 3.0 ng/mL (rather than 4.0 ng/mL). In such studies, PSA measurements above 2.5 or 3.0 ng/mL are considered elevated. Researchers hope that using these lower cutoff levels will increase the chance of detecting prostate cancer; however, this method may also increase overdiagnosis and false-positive test results and lead to unnecessary medical procedures. (See ERSPC trial results above.)
10. What other methods are being studied to detect prostate cancer?
Researchers are investigating several other ways to detect prostate cancer that could be used alone or together with the PSA test and DRE. Some of these include the following:
- MicroRNA patterns: MicroRNAs are small, single-strand molecules of ribonucleic acid (RNA) that regulate important cellular functions. Researchers have found that the pattern of microRNAs in a cell can differ depending on the type of cell and between healthy cells and abnormal cells, such as cancer cells. Some research also suggests that the microRNA patterns in early-stage prostate cancer and late-stage prostate cancer may be different.
- Non-mutation gene alterations: The activity of a gene can be altered in ways that do not involve a change (mutation) to its DNA code. This can occur by modifying the gene’s DNA through a process known as methylation or by modifying the proteins that bind to the gene and help control how it is configured in the chromosome on which it is located. These types of gene alterations are called epigenetic alterations. Research has already shown that certain genes become hypermethylated and inactivated during the development and progression of prostate cancer. Scientists hope to identify DNA methylation changes and protein modifications that will be able to identify prostate cancer early and help predict tumor behavior.
- Gene fusions: Sometimes genes on different chromosomes can come together inappropriately and fuse to form hybrid genes. These hybrid genes have been found in several types of cancer, including prostate cancer, and may play a role in cancer development. The gene fusions found in prostate cancer involve members of the ETS family of oncogenes, which are genes that cause cancer when mutated or expressed at higher than normal levels. Researchers are investigating whether diagnostic or prognostic tests based on gene fusions can be developed.
- PCA3: PCA3, also known as DD3, is a prostate-specific RNA that is reported to be expressed at high levels in prostate tumor cells. It does not appear to contain the genetic code for a protein. A urine test for this RNA, to be used in addition to current prostate cancer screening tests, has the potential to be useful and is under study.
- Differential detection of metabolites: Molecules produced by the body’s metabolic processes, or metabolites, may be able to help distinguish between benign prostate tissue, localized prostate cancer, and metastatic prostate cancer. One such molecule, known as sarcosine, has been identified and may be associated with prostate cancer’s invasiveness and aggressiveness. Ongoing research is investigating whether a test based on sarcosine can be developed.
- Proteo-imaging: Proteo-imaging is the ability to localize and follow changes at the molecular level, through imaging, of the protein distributions in specific tissues. Being able to see different patterns of protein expression in healthy prostate tissue versus abnormal prostate tissue may help classify early prostate changes that may one day lead to cancer.
- Protein patterns in the blood: Researchers are also studying patterns of proteins in the blood to see if they can identify one or more unique patterns that indicate the presence of prostate cancer and allow more aggressive cancers to be distinguished from less aggressive ones.
Article from http://www.cancer.gov/
SAN DIEGO—Almost half of all patients diagnosed with prostate cancer could be treated using active surveillance (AS) based on National Comprehensive Cancer Network (NCCN) guidelines, but fewer than 10% actually receive this treatment strategy, data from a recent study suggest.
The investigation, which was conducted by researchers from Tufts Medical Center and Tufts University in Boston, used information from the Surveillance Epidemiology and End Results (SEER) database on 37,646 men diagnosed with non-metastatic PCa in 2006 who had sufficient information on their T-stage, PSA, and Gleason score. Based on NCCN guidelines, the researchers determined the proportion of men for whom AS could be recommended as either the sole treatment strategy or one of the treatment options, and they compared this number with the actual number of men who were treated with AS.
A total of 12,183 patients were categorized as having low-risk disease. AS should have been the only treatment for 2,941 of them, yet only 712 (24%) were actually managed with this strategy. Twenty-five percent received external beam radiation therapy (EBRT), 20% received brachytherapy, 3% received EBRT plus brachytherapy, and 18% underwent radical prostatectomy (RP).
AS was an accepted treatment option (among other choices) for 9,242 low-risk patients, according to the investigators. Of these, 1,624 (18%) received AS, while 17% were treated with EBRT, 21% were treated with brachytherapy, 3% were treated with EBRT and brachytherapy, and 35% were treated with RP. In the intermediate-risk group, AS was an accepted option for 5,084 patients, of which 1,281 (25%) received the treatment. Others in the group received EBRT (29%), brachytherapy (9%), EBRT plus brachytherapy (6%), or RP (24%). The NCCN guidelines do not recommend AS for high-risk patients or those with locally advanced disease.
When looking at the total study sample of 37,646 men, the researchers found that 46% could have been managed with AS according to NCCN guidelines, and 9.6% actually received it. Extrapolating these percentages across the total number of patients with prostate cancer annually in the U.S. (192,000), the researchers determined that 88,000 patients could initially be treated with AS, while 18,000 received the treatment in 2006, leaving an additional 70,000 patients who could be treated with the strategy but are not.
Lead study author Tomas Dvorak, MD, of the department of radiation oncology at Tufts Medical Center, noted that despite these published figures, practice patterns will be slow to change. “Treatment decisions about active surveillance versus surgery or radiation are made at the individual patient-physician level, and as long as the current health care dynamics remain the same, I doubt active surveillance will be presented as a valid treatment choice to many patients,” Dr. Dvorak. In the United States, he said, patients often want “every treatment possible for their disease,” while physicians are concerned about missing a chance to cure a patient “who might develop incurable disease during the surveillance process.” Finally, he commented that financial aspects also come into play, since physicians are not compensated for monitoring a patient. From the February 2011 Issue of Renal And Urology News
Article from http://www.renalandurologynews.com/
Retirement-age men with slow-growing prostate cancer may wish to consider monitoring their disease rather than being treated immediately, according to a new study led by investigators at Dana-Farber Cancer Institute and Massachusetts General Hospital (MGH).
The study results, to be published in the Dec. 1 issue of the Journal of the American Medical Association, provide information to the thousands of American men in the 65-year-old age range who each year face the decision of how to deal with newly diagnosed prostate cancer when the cancer has characteristics that suggest a very low risk of spreading beyond the prostate.
Because there is limited information comparing outcomes of treatment options for low-risk disease, investigators developed a computer model simulating hypothetical patients whose quality of life and response to treatment were based on reports in medical literature.
“The analysis demonstrates that for this group of prostate cancer patients, a course of ‘active surveillance’ in which patients receive a blood test (PSA) every three to six months, a physical exam every six months, and periodic re-biopsies of their tumor tissue is a reasonable alternative to immediate treatment in terms of quality of life,” says study lead author Julia Hayes, MD, of Dana-Farber and the MGH Institute for Technology Assessment.
If surveillance reveals that the cancer has become more of a threat, it can then be treated.
Every year, about 200,000 men are diagnosed with prostate cancer in the United States, 90 percent of whom receive immediate treatment, which can include surgery, hormonal treatment, or radiation therapy.
However, in more than 70 percent of men with prostate cancer, the disease is low-risk, meaning it is unlikely to become life-threatening, and may not require immediate treatment.
“In recent years, active surveillance has emerged as an alternative to initial treatment for men with this type of prostate cancer,” Hayes says.
“But, while clinical studies are under way comparing active surveillance to front-line treatment, it will be years before they yield definitive results. The computer model we created allows us to anticipate those studies’ findings, and provides information to help men and their physicians negotiate this difficult decision.”
“Our analysis showed that 65-year-old men with low-risk, localized prostate cancer who chose active surveillance had a higher quality of life than those who received surgery or radiation right away, in part because they were able to avoid or delay adverse effects of treatment,” she states.
Patients approach the decision with different sets of preferences: some may be anxious about leaving the disease untreated; others may be more concerned about the potential side effects of treatment, which can include urinary incontinence, erectile dysfunction, and bowel disturbances.
When these patient preferences were changed in the model, the results of the model changed, in some cases favoring initial treatment.
Therefore, the authors urge patients to discuss these issues with their families and doctors in order to choose the approach that best reflects their own preferences and values.
In the study, researchers used a measure called Quality-Adjusted Life Expectancy (QALE) to compare active surveillance to initial treatment.
“QALE takes into account both the quality and length of each patient’s life,” explains the study’s senior author, Pamela McMahon, PhD, of the Institute for Technology Assessment at MGH.
“It weighs the benefits and side effects of treatment, as well as how men feel about being treated or not being treated. It’s an attempt to capture the physical and psychological aspects of disease and its treatment as thoroughly as possible.”
One of the main surprises of the study was that active surveillance held its edge over immediate treatment from a quality-of-life standpoint even when researchers entered data into their computer model that exaggerated any negative health effects of active surveillance, Hayes says.
“Thousands of men each year face the decision of whether to be treated immediately for low-risk prostate cancer or use active surveillance,” McMahon says. “Our study offers them evidence that can be a useful starting point for discussions with their families and doctors.”
The study was conducted as part of a series of comprehensive analyses of the comparative effectiveness of active surveillance versus treatment for men with low-risk prostate cancer conducted by the Institute for Clinical and Economic Review (ICER), based at MGH’s Institute for Technology Assessment.
ICER has also produced a website for low-risk prostate cancer patients based on these analyses to aid patients in their decision-making.
The study was funded in part by grants from the National Cancer Institute, the U.S. Department of Defense, and the Prostate Cancer Foundation, and by funding from the Blue Shield of California Foundation.
Co-authors of the study are: Philip Kantoff, MD, and Christopher Sweeney, Dana-Farber; Daniel Ollendorf, MPH and Steven Pearson, MD, of ICER; Michael Barry, MD, and James Stahl, MD, of MGH; Susan Stewart, PhD, Harvard University Interfaculty Program for Health Systems Improvement and the National Bureau of Economic Research; and Vibha Bhatnager, MD, University of California San Diego.
Article from http://www.dana-farber.org/