Posts Tagged ‘American Medical Association’

Breast cancer: Advances in prevention, diagnosis, and treatment

By Tyrone M. Reyes, M.D.

The past five years have brought discovery and advancement in all aspects of breast cancer. More importantly, these advances have resulted in not only better diagnosis and treatment but more individualized care as well. There’s no longer a one-treatment-fits-all approach to breast cancer. Instead, a team of doctors from various specialties is able to work together to tailor a treatment plan for each person based on many factors, such as cancer type, its stage and one’s personal biology (please refer to last week’s column).

The good news is that breast cancer survival rates are among the highest of all cancers. Overall, nearly 89 percent of women diagnosed with breast cancer live for at least five years after treatment. If caught at the very earliest stage — known as carcinoma in situ — that percentage goes up to 98 percent.

Lifestyle Factors

New research has revealed that certain lifestyle factors can reduce your risk of developing breast cancer, including:

• Exercise. Studies have shown that women who exercise about 30 minutes three or four times a week can decrease their breast cancer risk by about 26 percent.

• Alcohol. Studies have also shown that women who drink one or two alcoholic drinks a day increase their risk by 10 percent. That number goes up to 30 percent if you drink three or more alcoholic beverages a day.

• Weight. A study published in the Journal of the American Medical Association in 2006 concluded that women who lost 22 pounds after menopause reduced their risk of developing breast cancer by 45 percent.

Newer Technology

When an abnormality, such as a lump, is detected in the breast, your doctor will order tests or procedures to further evaluate the problem. These may include a diagnostic mammogram, ultrasound, magnetic resonance imaging (MRI), a needle biopsy or aspiration, or a formal surgical biopsy. These can help to determine if an abnormality is breast cancer, and if so, to characterize the tumor.

Technology has brought about new ways to see into the body, but to date, the mammogram is still the standard of care for screening and is the only screening test shown to decrease the chance of dying of breast cancer. Annual screening mammograms have been shown to decrease mortality by 20 to 30 percent in women over the age of 50. The American Cancer Society recommends that woman have regular mammograms beginning at age 40.

Other imaging technologies are used to complement mammography or to further evaluate an abnormality in the breast. Each offers benefits, but also shortcomings. These include:

• Magnetic resonance imaging (MRI). MRIs are particularly useful to evaluate abnormalities in women with dense breasts. Recently, several cancer organizations have made recommendations that women, who are at very high risk of developing breast cancer, get an annual MRI in addition to a mammogram. However, MRIs aren’t recommended for routine screening. That is because they’re expensive, require an IV injection of a contrast agent, and can lead to additional biopsies and give a high rate of false positives and increased anxiety.

• Ultrasound. Often, this is ordered to determine if a lump or suspicious area found during a breast exam or on a mammogram, is a cyst or a solid mass.

• Digital mammography. The use of this method is on the rise. Digital mammography is slightly better in younger women with dense breast tissue. It can decrease radiation dose and decrease the frequency of repeat images. It has the advantage of decreased waiting time since there’s no time needed to develop the film.

Other tests include computer-aided mammography, nuclear tracers, 3-D mammography, optical imaging, optoacoustic tomography, and microwave imaging.

Chemotherapy

This refers to drugs that kill cancer cells. It’s given alone or as several drugs together. In some cases, it has been found to be of benefit to give chemotherapy prior to surgery (neoadjuvant chemotherapy) to shrink a tumor. It is used for this purpose in women with large tumors. The technique has also been shown to significantly decrease the chance of the cancer returning, and allows women to live longer. Chemotherapy can have significant side effects, so doctors try to individualize treatments.

Genetic markers from the blood can identify which women are likely to have a good response to certain medications. Testing the genetic makeup of the tumor itself can help determine which women are at the highest risk of recurrence and which of those women are more likely to benefit from chemotherapy, while allowing women at very low risk of recurrence to avoid the side effects of unnecessary treatment.

The cancer cells can also be tested for the presence of the human epidermal growth factor receptor 2 (HER-2). HER-2 is a protein found in excessive amounts on the surface of about one out of three breast cancers. Those cancers have always tended to be more aggressive, more likely to spread, and less likely to respond to traditional chemotherapy. However, new treatments — such as the drug trastuzumab (Herceptin) — that directly target the HER-2 protein are now available, greatly improving the outlook for these women. Tratuzumab reduces post-surgical cancer recurrence by up to 50 percent for women with HER-2-positive cancers.

If your cancer is considered “hormone receptor positive,” hormone therapies with the use of estrogen blockers such as tamoxifen, anastrazole (Arimidex), letrazole (Femara) and exenestane (Aromasin), can reduce the rates of recurrence.

Radiation

Studies have shown success in two particular types of therapies — partial breast irradiation and short-course radiation. Both therapies reduce the amount of time you spend at the radiation center. In a traditional radiation course, you’ll spend about five days a week for five to six weeks receiving radiation to the breast.

Partial breast radiation is a new method of radiation that may be considered for those who have had a lumpectomy — a surgical option for small tumors relative to the size of the whole breast. In partial breast irradiation, radiation is focused on just where the tumor was before being removed through surgery.

Those with early-stage cancer and no lymph node involvement — but who don’t qualify for partial breast radiation, due to factors such as tumor size or location — may be candidates for short-course radiation. A Canadian study released in 2008 concluded that reducing radiation treatments for certain early-stage breast cancer to 16 sessions given over the course of about three weeks appears to be just as effective as the standard treatment series of 25 treatments over five weeks.

Surgical Treatment Options

If a mastectomy is recommended by either a breast surgeon or an oncologist — or is preferred by the patient — there are several types of breast removal. These include:

• Total, or simple, mastectomy. This involves removal of breast tissue, skin, the nipple and the dark skin (areola) around the nipple but not the lymph nodes.

• Modified radical mastectomy. This removes the same tissues as does a total mastectomy, but also includes the lymph nodes under the armpits (axillary lymph node dissection).

• Radical mastectomy. This is the most extensive form of mastectomy. In addition to the removal of breast and lymph nodes, some chest wall muscle, and additional fat and skin also are removed.

• Others. This includes the skin-sparing mastectomy and the subcutaneous (nipple-sparing) mastectomy.

On The Horizon

Experts expect to see greater individualization of treatment based on a greater understanding of the genetic factors that govern breast cancer biology. More specific abnormal pathways of cancer cells and how to target these with therapy will be identified.

Studies already in progress include genetic research on breast cancer genes and new imaging techniques. Scientists also anticipate that additional drug and hormone discoveries will be made which will be valuable in terms of cancer prevention.

Source: Philstar.com

Mediterranean Diet and Physical Activity Reduce Alzheimer’s Risk

 Previous studies have shown that a Mediterranean diet and higher physical activity are each associated with a lower risk of Alzheimer’s disease.

However, the combined association of Mediterranean diet and more physical activity on Alzheimer’s risk is not well-studied. In the August 12, 2009 issue of Journal of the American Medical Association, researchers report that both eating well and participating in physical activity may independently confer Alzheimer’s disease-related health benefits.

 

Researchers from Columbia University studied 1880 community-dwelling elderly individuals living in New York City who did not have Alzheimer’s dementia. Both diet and physical activity information were available for each of these individuals. The researchers administered neurological and neuropsychological testing approximately every 1.5 years from 1992 through 2006. During this time, a total of 282 cases of Alzheimer’s disease were diagnosed. Both Mediterranean diet and higher levels of physical activity were associated with a lower risk of Alzheimer’s disease.

 

While some may argue that the association between physical activity and Alzheimer’s disease simply reflect that more physically active people are also more likely to eat healthier, this study demonstrates that the associations of diet and physical activity with lower rates of Alzheimer’s disease were independent of each other. Based on this study, even a relatively small amount of physical activity (1.3 hours of vigorous physical activity or 2.4 hours of moderate physical activity or 4 hours of light physical activity per week) was associated with a reduction in Alzheimer’s risk.

 

Source:

JAMA. 2009;302(6):627-637.

Created on: 08/20/2009
Reviewed on: 08/20/2009

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Does Mediterranean Diet Slow Cognitive Decline?

Following a Mediterranean diet has been linked to a lower risk of death and chronic diseases, but the association between Mediterranean diet and dementia risk is more controversial.

In the August 12, 2009 issue of Journal of the American Medical Association, researchers report on a study in which higher adherence to a Mediterranean diet was associated with slower cognitive decline, but only on one neuropsychological test on a consistent basis.

 

Columbia University Medical Researchers and their French colleagues studied 1410 French adults who were at least 65 years of age in order to investigate the association between a Mediterranean diet and changes in cognitive performance and the risk for dementia. Each of the study participants underwent 4 neuropsychological tests to evaluate cognitive performance. After adjusting for age, gender, level of education, marital status, and other dementia risk factors, the researchers found that adherence to a Mediterranean diet was associated with fewer errors on the Mini-Mental State Examination (MMSE). However, performance on three other neuropsychological tests was not consistently associated with Mediterranean diet.

 

The researchers also reported that adherence to a Mediterranean diet was not associated with the risk for incident dementia, however the statistical power of this finding was limited. So, it seems that the association among Mediterranean diet, cognitive decline, and dementia risk still requires further study.

 

Source:

JAMA. 2009;302(6):638-648.

Created on: 08/19/2009
Reviewed on: 08/19/2009

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Spinal Tap May Be Able to Predict Alzheimer’s Disease

 Small studies have previously shown that biomarkers in the cerebrospinal fluid, the fluid surrounding the brain and spinal cord, may be useful in identifying which patients with mild cognitive impairment will go on to develop Alzheimer’s disease.

Now, as reported in the July 22/29, 2009 issue of the Journal of American Medical Association, three cerebrospinal fluid (CSF) biomarkers identify incipient Alzheimer’s disease with good accuracy.

 
This study involved a total of 750 individuals with mild cognitive impairment, 529 individuals with Alzheimer’s disease, and 304 controls, all recruited from 12 centers in Europe and the United States. Individuals with mild cognitive impairment were followed for a period of at least 2 years or until they had progressed to dementia. During follow-up, 271 study participants with mild cognitive impairment progressed to Alzheimer’s disease and 59 others were diagnosed with other types of dementia. Three CSF biomarkers, Aβ42,T-tau, and P-tau, were found to be accurate in identifying early-stage Alzheimer’s disease. However, the accuracy reported in this multi-center study was less than that reported in prior single center studies, perhaps due to variability in the assays used to analyze the CSF biomarkers.
 
The ability of CSF biomarkers to accurately identify incipient Alzheimer’s disease has significant clinical implications, since the underlying disease process of Alzheimer’s disease begins long before symptoms progress to dementia. Early identification of Alzheimer’s disease would allow for even earlier initiation of medical interventions that could slow the progression of this debilitating condition.
 
 

Source:

JAMA. 2009;302:385-393.

Created on: 08/04/2009
Reviewed on: 08/04/2009

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Vitamin pills don’t prevent heart disease

NEW ORLEANS (AP) — Vitamins C and E do nothing to prevent heart disease in men, one of the largest and longest studies of these supplements has found.

Vitamin E even appeared to raise the risk of bleeding strokes, a danger seen in at least one earlier study.

Besides questioning whether vitamins help, “we have to worry about potential harm,” said Barbara Howard, a nutrition scientist at MedStar Research Institute of Hyattsville, Maryland.

She has no role in the research but reviewed and discussed it at an American Heart Association conference. Results also were published online by the Journal of the American Medical Association.

Male smokers taking vitamin E had a higher rate of bleeding strokes in a previous study, and several others found no benefit for heart health. (more…)

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