By David Liu, PH.D.

Saturday Feb 11, 2012 (foodconsumer.org) -- A new study in a Feb 8, 2012 issue of JAMA finds that older postmenopausal women diagnosed with hormone receptor-positive breast cancer were more likely to die from the disease than their younger peers.

The study led by Willemien van de Water, MD of Leiden University Medical Center in Leiden, the Netherlands and colleagues shows that women who were diagnosed with breast cancer at age between 65 and 74 years old were 25 percent more likely to die than those who were diagnosed with the disease at age younger than 65.

The death risk for those who were older than 75 at the time of diagnosis was increased by 63 percent, compared to those who were diagnosed with the disease at age younger than 65.

The study was intended to assess the association between age at diagnosis and breast cancer outcome in postmenopausal patients with hormone receptor-positive breast cancer. A total of 9766 patients were enrolled in the TEAM (Tamoxifen Exemestance Adjuvant Multinational randomized clinical trial conducted between Jan 2001 and Jan 2006.  

The patients were followed up for approximately 5.1 years.   Patients who died after 5 years of treatment were considered a survivor, meaning that she does not die from this disease, which is the way the medical circle evaluates the efficacy of a treatment.

During the follow-up, 1,043 patients died, of whom 78 percent were found in the group of 5349 patients aged younger than 65, 56 percent found in the group of 3060 patients aged 65 to 74 and 36 percent in the group of 1357 patients aged 75 or older.

Statistical analyses found that compared with patients younger than 65 patients, those aged 65 to 74 years were at 25 percent increased risk of dying from breast cancer while those aged 75 or older were at 63 percent increased risk of dying from the breast cancer.

Similarly, risk for breast cancer relapse slightly increased with age for patients aged 65 to 74 years (7 percent), compared to the group of younger patients. In comparison, those aged 75 or older were 29 percent more likely to have relapse.

Risk of dying from other causes also increased with age.  Patients aged 65 to 74 years were 166 percent more likely to die from other causes and those aged 75 or older were 630 percent more likely to die from other causes, compared to those aged 65 or younger.

Women  diagnosed with hormone receptor positive breast cancer are often given tamoxifen for five years.  It's believed that tamoxifen is able to interfere with the cancer-promotional effect of hormone estrogen on breast tumor in a way, which doctors believe reduces the risk of relapse, which is a cause for breast cancer death.

Breast cancer is expected in one in eight American women. Each year the disease is diagnosed in about 200,000 women in the U.S, and the disease and its complications kill about 5000 to 6000 of breast cancer patients, according to the National Cancer Institute.

Breast cancer is largely a preventable disease.  Many lifestyle parameters can be modified to drastically reduce the risk.  Using hormone replacement therapy, contraceptives or birth control pills, eating too much meat and dairy products, suffering chronic vitamin D deficiency, performing night-shift work, having chronic emotional or mental stress from jobs and relations, giving birth at an older age or never having a child can boost risk of breast cancer.