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.

Should I get a PSA test for prostate cancer?

A new study shows that screening for prostate cancer doesn’t necessarily save lives

Prostate cancer screening is about to get a whole lot cloudier.

Published this morning in the NEJM, the results of the study by the National Cancer Institute showed that, for men who were screened with both a PSA and digital rectal exam, there was no difference when compared to men who received “usual care.”

The results confirm the suspicions that many physicians already had, namely, that screening for prostate cancer does not appear to save lives.

As I have written countless times, there are many other diseases that can raise a PSA level. Combined with the fact that physicians have to act on elevated levels, this can lead to excessive prostate biopsies, as well as treating early cancers that end up not being the ultimate cause of death. All of these procedures expose the patient to a host of side effects, including bleeding and infection from the biopsy, and impotence and urinary incontinence from prostate cancer treatment.

The study was paired with the findings from a concurrent European study, which was not quite as negative. Nonetheless, the benefit of prostate cancer screening was minimal, with “7 fewer prostate cancer deaths for every 10,000 men screened and followed for nine years.”

Already, the USPSTF is shying away from endorsing prostate cancer screening by updating their guidelines last year, no longer recommending a PSA test for men older than 75.

So, what to do if you’re a patient? I think it’s more imperative than ever not to accept the dogma that “more screening is better medicine.” If anything, the decision of obtaining a PSA test needs to be thoroughly discussed with your doctor. Suddenly, the benefits of going down the path of screening doesn’t necessarily outweigh the risks.

Many may find that counterintuitive, and to be honest, it’s a hard truth to swallow. But these findings can help counter the pervading myth that obtaining every conceivable screening test is a sure way to improve health, when in actuality, it isn’t.

Routine Prostate Cancer Screening With PSA Test

Two papers published on bmj.com today report that there is unsatisfactory evidence to support population-wide screening for prostate cancer using the prostate specific antigen (PSA) test.

The PSA test cannot differentiate lethal from harmless prostate cancer, according to the authors. This could lead to over diagnosis and overtreatment of healthy men.

Prostate specific antigen (PSA) is a protein formed in the cells of the prostate gland. It is present in small quantities in the blood of healthy men. It is frequently elevated in men with prostate cancer and in men with benign prostatic enlargement.

Although it remains controversial, PSA screening is commonly used in many countries. The latest study suggests that prostate cancer deaths were lower among screened men but at a cost of significant over diagnosis and treatment.

A Swedish team of researchers set out in the first study to evaluate how well prostate specific antigen predicted a potential prostate cancer diagnosis.

They used PSA test results from 540 men diagnosed with prostate cancer measured several years before diagnosis and from 1,034 healthy controls. Results indicated that the PSA test did not reach the probability ratios. It is a measure used to predict disease required for a screening test. Only very low concentrations of PSA (less than 1ng/ml) virtually ruled out a diagnosis of prostate cancer during monitoring.

The researchers inform that there is a need for other biomarkers for early detection of prostate cancer and before population based screening for prostate cancer should be introduced.

US researchers looked at the benefits and risks of PSA screening in a second analysis paper. They concluded that data on costs and benefits remain insufficient to support population based screening. In addition, they recommend further accurate measuring of the financial and psychological costs of false positive results, over diagnosis and overtreatment of prostate cancer.

In conclusion, they consider that men should be entirely informed of the benefits, harms and uncertainties associated with the PSA test before they are screened.

This observation is supported in a complementary editorial by researchers at Monash University in Australia.

Dr Dragan Ilic and Professor Sally Green write: "Clinicians and patients are faced with many uncertainties when considering whether or not to undergo prostate screening."

They remark: "Further research is required to develop and evaluate a valid screening test for prostate cancer." Until such a test exists, the choice to undertake screening should follow a shared decision making approach

The PSA Test - How Does It Work

The purpose of this article is to remove some of the mystery surrounding the PSA test and its use in signaling the potential presence of prostate cancer.

The cells of the prostate gland produce prostate-specific antigen. A rectal exam and a PSA (prostate-specific antigen) test will help detect prostate cancer in men age 50 or over. The Federal Drug Administration approved the use of the PSA test to detect prostate cancer and to see if the cancer has recurred. A high PSA level is a sign that cancer is present. There are other reasons for a high PSA level and PSA screening has some limits.

The PSA test measures the level of protein produced by the prostate gland. The doctor will take a blood sample and send it to a laboratory. This test is sometimes called a biological marker for cancer tumors. Men normally have low levels of PSA in their blood. If the rate is high, it could point to prostate cancer but it can mean there are other non-cancer conditions present in the prostate. As men get older, prostate cancer and other prostate problems become more of a problem. Enlarged prostate and prostatitis may raise the PSA levels in the blood. Neither of these problems causes cancer but it is possible for a man with one of these problems to develop prostate cancer.

The PSA level will not tell the doctor if the patient has a benign prostate problem or cancer. The doctor will use the PSA test to decide if there should be a check for other signs of prostate cancer.

The Federal Drug Administration approved the PSA test to be used with a rectal exam to check for any abnormalities in the prostate. The doctor will insert a gloved finger into the rectum to check for lumps or areas that seem abnormal. The PSA test is used with this rectal exam to detect cancer in men, especially those who have no symptoms. The FDA also approved the test for patients who have had prostate cancer to see if the cancer has come back.

The PSA test is highly recommended for men over the age of 50. If the patient has a high risk factor for prostate cancer, the doctor may recommend PSA testing to start at age 45. There are some risk factors a man should look at if a doctor recommends routine screening. Age is the most common risk factor, but if there is a family history of prostate cancer you have a greater chance of having it too. African-American has the largest risk of contacting prostate cancer. Native American and Asian men have the lowest rates of this disease. Some think this might be because a diet that is high in animal fat may increase the chance of getting prostate cancer.

If a man shows a high PSA level in his blood the doctor may look for other causes before doing more screening for prostate cancer. If the patients have no other symptoms, you may be advised to watch for any changes in urination habits and take another PSA test in a few months.

So, in summary, pros and cons of the PSA test?

Possible benefits of having the test

* It may provide reassurance if the test result is normal.

* It can help to detect prostate cancer before any symptoms develop.

* Treatment in the early stages of prostate cancer could help you live longer and avoid the complications of cancer (although there is no good evidence that this is so).

Possible disadvantages

* It might detect a slow-growing cancer that may never cause any symptoms or shorten your life span. But the diagnosis of 'cancer' may cause you significant anxiety which could affect your quality of life.

* It may lead you to have treatment for early prostate cancer which might not help you live longer. Also, the main treatments for early prostate cancer do carry some risk and can cause side-effects.

* It could miss cancer in the prostate, and falsely reassure you that all is well.

* It could lead to anxiety and a biopsy when you have no cancer.

Ultimately, the decision should be taken by yourself in conjunction with your GP who can advise further and who knows your particular circumstances.