Study: Breast cancer survival rate better with more muscle mass

April 9 (UPI) — Breast cancer patients with higher muscle mass have a greater survival rate, according to a statistical analysis.

Doctors at Kaiser Permanente and the Dana Farber Cancer Institute in Boston tracked 3,241 women who were diagnosed with stage II or stage III breast cancer between 2000 and 2013, finding that age-related muscle loss and more fat were linked to a statistically lower survival rate. Their findings were published Thursday in the Journal of the American Medical Association Oncology.

“To our knowledge, this is the largest study to date of patients with nonmetastatic breast cancer, and we demonstrate that sarcopenia is underrecognized, highly prevalent, and is associated with a significant increased risk of death,” wrote the researchers, who noted more than a third of newly diagnosed patients have sarcopenia.

The average age of the study participants was 54.

Study participants who had sarcopenia, or age-related muscle loss, showed a 41 percent greater mortality rate, according to the statistic analysis by the researchers. And patients with the greatest amount of body fat, called adipose tissue, had a 35 percent higher rate.

Sarcopenia was found in 1,086 patients, or 34 percent of participants. The rate of low muscle radiodensity was identified in 1,199 patients or 37 percent.

The survival rates were regardless of a woman’s age or cancer stage, the researchers said.

The normal body mass index for a woman is 18.5 to 24.9, according to the American Cancer Society.

“Muscle and fat mass assessed from clinically acquired CT scans are more strongly associated with survival than BMI, suggesting these would be more useful in identifying women at risk of poor survival due to adiposity,” the researchers wrote.

“Furthermore, we also show that sarcopenia and adiposity are both important risk factors and should be considered together when assessing risk. These prognostic measures can be easily integrated into routine clinical care using new software to generate highly accurate measures of body composition from clinically collected CT scans.”

The participants were followed up over six years with 619 of them dying.

“In addition to weight loss, we should also consider interventions to improve muscle mass, such as resistance training or protein supplementation,” the researchers wrote. “In the era of precision medicine, the direct measurement of muscle and adiposity will help to guide treatment plans and interventions to optimize survival outcomes.”

The U.S. Department of Agriculture recommends women should get 46 grams of protein per day, which is about 7 ounces of meat, chicken or fish.

The USDA says that “in general, 1 ounce of meat, poultry or fish, 1/4 cup cooked beans, 1 egg, 1 tablespoon of peanut butter, or 1/2 ounce of nuts or seeds can be considered as 1 ounce-equivalent from the Protein Foods Group.”