According to National Cancer Institute estimates, there were about 252,710 new diagnoses of breast cancer in the United States in 2017. The life expectancy following treatment for this type of cancer is quite good, with a 5-year survival rate of 89.7 percent.
However, cancer treatment is often associated with the onset of metabolic syndrome, a cluster of related conditions including heart disease, hypertension, obesity, high blood sugar, and insulin resistance. Metabolic syndrome has also been linked to a poorer survival rate among breast cancer survivors.
That is why researchers from the University of Southern California in Los Angeles, CA, have set out to see how post-treatment life expectancy might be prolonged through regular exercise, which can help to tackle or prevent the onset of metabolic syndrome.
“In breast cancer patients, metabolic syndrome is exacerbated by obesity, a sedentary lifestyle and receipt of chemotherapy,” Dieli-Conwright explains.
In their paper, the authors also note that individuals experiencing metabolic syndrome have a 17 percent higher chance of being diagnosed with breast cancer. They may also be more likely to experience cancer recurrence after treatment, and may have a shorter life expectancy.
Taking these considerations into account, the research team hypothesized that adherence to a regular exercise schedule might improve the long-term survival rate by addressing weight gain and its associated disorders
Dieli-Conwright and team conducted a randomized trial, working with 100 individuals who had successfully undergone breast cancer treatment less than 6 months before the study was due to begin.
At the start of the study, approximately 46 percent of participants were deemed obese, while approximately 77 percent had been diagnosed with metabolic syndrome.
The intervention consisted in three weekly one-on-one training sessions over a period of 4 months, including weight-lifting exercises and a minimum of 150 minutes of moderate aerobic exercise.
The researchers also noted that the women who participated in the fitness program gained muscle mass and shed excess fat and that regular exercise reduced participants’ risk of developing heart disease.
Moreover, fitness program participants also saw a 10 percent decrease in blood pressure and a 50 percent increase in high-density lipoprotein (HDL), or the so-called “good cholesterol,” which absorbs other types of cholesterol, carrying them back to the liver to be eliminated from the system.
Dieli-Conwright points out that obesity can cause inflammation, which, in turn, might facilitate tumor growth and cancer recurrence following treatment.