Thursday, March 27, 2008

Preventing Alzheimer's - Exercise still best

A report last week from the Alzheimer's Association predicts that 10 million baby boomers will develop Alzheimer's disease in the United States — that translates to one out of every eight. For us "baby boomers," this is frightening to say the least.

There are new treatments on the horizon, but we all wonder whether or not they will be available in time for us or even our children. Let's keep hoping for a cure or prevention model by supporting research in whatever way we can. Meanwhile, studies continue to point to physical exercise as the most effective therapy today to prevent Alzheimer's.

Mounting evidence suggests that physical activity may have benefits beyond a healthy heart and body weight. Through the past several years, population studies have suggested that exercise which raises your heart rate for at least 30 minutes several times a week can lower your risk of Alzheimer's. Physical activity appears to inhibit Alzheimer's-like brain changes in mice, slowing the development of a key feature of the disease.

In one observational study, investigators looked at the relationship of physical activity and mental function in about 6,000 women age 65 and older, over an 8 year period. They found that the women who were more physically active were less likely to experience a decline in their mental function than inactive women.

Another compelling study, conducted by researchers at the University of Chicago, was highlighted on ABC News last week. The study used mice bred to develop Alzheimer's type plaque in the brain. In the study, some mice were allowed to exercise and others were not. The brains in the physically active mice had 50 to 80 percent less plaque than the brains of the sedentary mice and they (exercising mice) produced significantly more of an enzyme in the brain that prevents plaque.

Monday, March 17, 2008

Cancer detected earlier with new technique

Doctors may one day be able to detect early stages of colon cancer without a biopsy, using a new technique developed by researchers at the Stanford University School of Medicine.

This imaging technology is one of many new ways of detecting cancers in the body in real time, said Christopher Contag, PhD, associate professor of pediatrics and of microbiology and of immunology, who led the study. Contag said he hoped it might be one of the first to be used routinely for early detection of cancer.

"Detecting colon cancers is just the first step," said Contag. He predicted similar techniques will eventually be able to find a wide range of cancers, monitor cancer treatment, and deliver chemotherapies directly to cancerous cells in the colon, stomach, mouth and skin. The study will be published online March 16 in Nature Medicine.

Colon cancer is the third most common cancer in men and women, with about 150,000 people diagnosed each year. Although colonoscopy isn't perfect, it's currently the best way of finding colon cancers when they are still at the most treatable stage.

If doctors find suspicious growths during a routine colonoscopy, they take a sample, called a biopsy, and send it to a pathology lab to screen for cancer. That step takes time and not all people have ready access to a nearby pathologist. What's more, doctors biopsy only the cancers that form easily visible growths called polyps. Early stage cancers that remain flat aren't detected.

The trick to picking up cancer without a biopsy is to find a way of seeing which cells are cancerous while they are still in the body. That's what Contag and his group succeeded in doing.

The group found a short protein that sticks to colon cells in the early stages of cancer. Before screening a person, they spray that short protein attached to a fluorescent beacon into the colon. The protein then gloms on to any cancerous cells and creates an easily visible fluorescent patch. They then used a miniaturized microscope called Cellvizio GI, developed by Paris-based Mauna Kea Technologies and loaned to Contag, to peer inside the colon and look for those telltale spots.

Not only did the researchers see fluorescent patches, they could make out the individual cancerous cells. That fine resolution could allow doctors to pick up the earliest possible cancers. Contag said it could also become a useful research tool for studying the small number of cancer stem cells that are thought to establish the eventual tumor.

In the initial trial with 15 patients, the technique detected 82 percent of the polyps that were considered cancerous by a pathologist. Contag said the next step is to work with some of the additional small proteins they've found that also attach to cancerous cells. He thinks that a combination of those proteins will make the technique highly accurate.

Once the screen is ready for widespread use, Contag said it could bring accurate cancer detection to people in remote locations who otherwise don't have access to pathology labs. "A doctor could send a video in real time via the Internet to someone trained to analyze the living cell images," Contag said. This could help people begin the appropriate therapy when the cancer is still at an early stage.

Contag thinks this technique, developed in part through the cancer imaging program at the Stanford Cancer Center, could also be adapted to detect cancers in the mouth, esophagus and stomach. In addition, real-time screening could be used as a way of assessing whether a chemotherapy regimen is working. Contag said that if a tumor responds to a given chemotherapy, changes in the cells might be visible immediately. That response could allow doctors to switch patients to a new, more effective treatment if the first one results in no improvement. Currently people go through several rounds of chemotherapy before the first screen to find out if the treatment is working, a delay that prevents people from moving on to an effective treatment as soon as possible.

Tuesday, March 11, 2008

Drinking may raise the risk of breast cancer

Even moderate drinking may raise the risk of breast cancer among postmenopausal women on hormone replacement therapy, new research suggests.

A number of studies have linked regular drinking to a higher risk of breast cancer; it's thought that the risk reflects the effects of alcohol on women's levels of estrogen and other hormones. Similarly, hormone replacement therapy (HRT) after menopause has been shown to raise the risk of breast cancer.

The new findings, reported in the International Journal of Cancer, suggest that alcohol and HRT may combine to further boost the odds of developing the disease.

Among the more than 5,000 Danish women researchers followed, those who were on HRT and averaged one or two drinks per day had a three-fold higher risk of breast cancer than women who neither drank nor took hormones.

Women who had more than two drinks per day had a nearly five-times higher risk of the disease.

In contrast, drinking habits were not related to breast cancer risk among women who did not use HRT, according to Drs. Naja Rod Nielsen and Morten Gronbaek of the Danish National Institute of Public Health, Copenhagen.

The findings, according to the researchers, raise the possibility that drinking affects postmenopausal breast cancer risk differently depending on women's hormone use. However, more studies are needed to confirm the interaction between alcohol and hormones, they write.

The findings come from two decades' worth of data on 5,035 postmenopausal women who were surveyed about their drinking habits and hormone use at the beginning of the study. Over the next 20 years, 267 women developed breast cancer.

Overall, regular drinking was linked to a slightly higher risk of the disease. But when the researchers considered hormone use, drinking affected breast cancer risk only among women who were on HRT at the outset.

In one previous study of postmenopausal women taking oral estrogen, those who drank were found to have estrogen levels that were three times higher than those of non-drinkers, Nielsen and Gronbaek note.

This may be one explanation for the higher breast cancer risk seen in this study, they write.

If further research confirms the findings, they conclude, there should be an impact on both HRT use and recommendations for "sensible drinking limits" among postmenopausal women.

Friday, March 07, 2008

Breast cancer patients can be treated safely

A new pilot study by investigators at Memorial Sloan-Kettering Cancer Center (MSKCC) found that breast cancer patients can be treated safely with a “dose-dense” regimen of standard chemotherapy agents and the antibody trastuzumab (Herceptin®), a drug that has previously been shown to cause cardiac toxicity. While previous reports evaluating the cardiac effects of breast cancer treatments including trastuzumab and anthracyclines have shown an acceptable safety margin, the new study demonstrates an even lower risk of cardiac toxicity when standard doses of these drugs are administered more frequently over time – a treatment plan called “dose-dense,” which has previously been shown to be a more effective anti-cancer approach.

The researchers used a dose-dense regimen of doxorubicin (Adriamycin®) and cyclophosphamide (Cytoxan® or Neosar®) followed by paclitaxel (Taxol®) and found that the regimen – when given every two weeks instead of three – pairs safely with trastuzumab, a drug that is used to treat breast cancer in women whose tumors contain the protein receptor called HER2.

According to the findings, only 1.4 percent (one patient) of the 70 early-stage breast cancer patients treated with this regimen experienced congestive heart failure after 28 months of follow-up. This rate of cardiac toxicity is lower than the 4 percent threshold that is generally considered acceptable, and still lower than what was found in larger, previously published trials evaluating conventionally scheduled treatment with the use of trastuzumab.

The study’s authors concluded that this dose-dense regimen combined with trastuzumab is a safe and effective way to treat women with early-stage HER2-positive breast cancer in the adjuvant setting and there is no need to forgo the use of this regimen because trastuzumab is also being administered.

Sunday, March 02, 2008

Pregnancy weight gain

Why do we care so much about pregnancy weight gain? The research on this subject is pretty clear. The incidence of pregnancy complications is higher in the upper and lower extremes of weight gain. Generally your health care provider will give you an idea of the amount of weight gain that is optimum for you and your baby.

So, what do you do the month you get on the scale and you find you gained 8 pounds? First, forgive yourself. Secondly, remember that the 8 pounds is history now. Look at the past weeks and see if you can pinpoint any major contributing factors to your pregnancy weight gain. Once you recognize possible causes you can find ways to deal with them.

If you find you are having real problems getting a handle on your pregnancy weight gain, see if there is a nutritionist or dietitian available for you to talk to about the problem. Enjoy your food. Your weight gain is one part of your pregnancy. Don't let the scale ruin your joy and enjoyment of this pregnancy.

There are women on the other side of the needle of the scale. You get on the scale thinking you'll have gained at least 3 pounds and instead you lost a pound or gained 1/2 a pound. My advice is the same. What can you learn from it looking back on your eating habits? Sometimes just changing to a healthier diet can cause a loss.