What`s new in prostate cancer research?
Research about prostate cancer is being done in many medical centers around the world.
New research on genes linked to prostate cancer helps scientists better understand how prostate cancer grows. Tests to find abnormal prostate cancer genes could also help tell which men are at high risk. They could then be tested more often. Further research will help provide answers about the chemical changes that lead to prostate cancer. This may make it possible to design drugs to target those changes.
One of the biggest problems now facing doctors and their patients with prostate cancer is figuring out which cancers are more likely to spread. Knowing this could help decide which men need treatment and which could be better served by watchful waiting. Researchers are now trying to find genetic clues about which cancers are more likely to grow fast and spread.
Researchers continue to look for foods that affect prostate cancer risk. Scientists have found some substances in tomatoes and soybeans that may help to prevent prostate cancer. They are trying to develop related compounds that are even more powerful and might be taken as supplements. So far, most research suggests that a balanced diet that includes these foods as well as other fruits and vegetables is better than taking these substances as supplements.
Some studies have suggested that certain vitamins and minerals could lower prostate cancer risk. But a large study of this issue, called the Selenium and Vitamin E Cancer Prevention Trial (SELECT), found that neither vitamin E nor selenium supplements lowered prostate cancer risk after daily use for about 5 years. In fact, men taking the vitamin E supplements were later found to have a slightly higher risk of prostate cancer.
Other recent studies have found that men with high levels of vitamin D seem to have a lower risk of getting the more lethal forms of prostate cancer. Overall though, studies have not found that vitamin D protects against prostate cancer.
Although many people believe that vitamins and other natural substances cause no harm, recent research has shown that high doses may be harmful. One study found that men who take more than 7 multivitamin tablets per week may have a higher risk of getting advanced prostate cancer.
Finding prostate cancer early
Doctors agree that the PSA blood test is not a perfect test for finding prostate cancer early. It misses some cancers, and in other cases the PSA can be high when there isn't any cancer. Researchers are working on ways to address this problem. While early results have been promising, new blood tests are not yet available outside of research labs and will need more study before they are widely used to test for prostate cancer. Other new tests being studied are urine tests.
Doctors doing prostate biopsies often use transrectal ultrasound (TRUS), which uses sound waves to create black and white pictures of the prostate. But standard ultrasound may not find some areas containing cancer. A newer method, known as color Doppler ultrasound may make prostate biopsies more accurate by helping to ensure the right part of the gland is sampled. But more studies are needed before its use becomes common. At this time, this test is only available as a part of a clinical trial. Doctors are also studying whether MRI can be used to help guide prostate biopsies.
Staging plays a key role in figuring out which treatment choices are best for a man. But scans such as CT and MRI can't find all cancers, especially cancer in lymph nodes. A new type of enhanced MRI might help find lymph nodes that contain cancer and make staging easier. Early results of this method look good, but it needs more study before it becomes widely used.
A newer type of PET scan may also be helpful in finding prostate cancer in different parts of the body, as well as helping to decide if treatment has been working. Studies of this technique are now in progress.
This is a very active area of research. Newer treatments are being developed, and current treatment methods are being improved.
Surgery: If the nerves that control erections must be removed during surgery, a man will become impotent. Some doctors are looking at how to repair these nerves with grafts of small nerves taken from other parts of the body or something artificial. This is still experimental and not all doctors think it is useful. Further studies are going on.
Radiation treatment: Better technology is making it possible to aim radiation more precisely than in the past. This makes it possible to treat only the prostate gland and any cancer just outside the gland. Studies are going on to find out which techniques are best for which patients.
New computer programs allow doctors to better plan the radiation doses and approaches for both external radiation therapy and brachytherapy.
Newer treatments for early stage cancers: Researchers are now studying newer forms of treatment for early stage prostate cancer, either as the first treatment or as treatment after unsuccessful radiation treatment.
One treatment, known as high-intensity focused ultrasound (HIFU), destroys cancer cells by heating them with highly focused ultrasonic beams. While it has been used more in Europe, it is not used outside of clinical trials in the United States at this time. Studies are now going on to find out if it is safe and effective.
Nutrition and lifestyle changes: One early study found that in men with a rising PSA after surgery or radiation therapy, drinking pomegranate juice seemed to slow the time it took the PSA level to double. Larger studies are now trying to confirm these results.
Some encouraging early results have also been reported with flaxseed supplements, which seemed to slow the rate at which prostate cancer cells multiplied. More research is needed to confirm this finding.
Another study found that men who chose not to have treatment for their localized prostate cancer may be able to slow its growth with major lifestyle changes. The men ate a vegan diet (no meat, fish, eggs, or dairy products) and exercised a lot. They also went to support groups and yoga. After 1 year the men saw a slight drop in their PSA level. It isn't known whether this effect will last since the study only followed the men for 1 year. Also, some men may find these changes hard to follow.
Hormone treatment: Several newer forms of hormone therapy have been developed in recent years. Some of these may be helpful even if standard forms of hormone therapy are no longer working. Some examples include abiraterone (Zytiga®) and enzalutamide (Xtandi), which were recently approved to help treat advanced prostate cancer. They are described in the section, "Hormone therapy for prostate cancer." Orteronel is another drug that worked will in early studies.
Chemotherapy: New chemo drugs and combinations of drugs are being studied. Some (such as docetaxel and cabazitaxel) have been shown to help men live longer.
Prostate cancer vaccines: Vaccines that boost the body's immune response to prostate cancer cells are being tested in clinical trials. One vaccine has been approved and is available now. Unlike vaccines against infections like measles or mumps, these vaccines are designed to help treat, not prevent, prostate cancer.
Blood vessel growth: In order for cancers to grow, blood vessels must grow to nourish the cancer cells. This process is called angiogenesis. Drugs that stop or slow the growth of these blood vessels are being studied for use against prostate cancer. Several of these drugs are now being tested in clinical trials.
Preventing or treating spread of cancer to the bones: Several newer medicines may help prevent or treat prostate cancer spread to the bones.
Doctors are also looking at a way to treat bone pain called RFA (radiofrequency ablation). RFA has been used for many years to treat tumors in other organs such as the liver. Its use for bone pain is still fairly new, but early results are promising.
Last Medical Review: 03/09/2012
Last Revised: 01/17/2013