New research presented at the Endocrine Society’s annual meeting found that nearly 20% of breast cancer survivors experience weight gain of more than 10% after their treatment. Weight gain is a common concern among survivors, but it also poses a risk factor for cancer recurrence and cardiovascular disease. Factors that contribute to this weight gain include having an initial lower weight, hormone-positive breast cancer, advanced cancer at diagnosis, younger age, BRCA2 gene mutations, chemotherapy, endocrine therapy, and aggressive breast surgery. Identifying these factors early on could improve outcomes for breast cancer survivors in the long term.
Breast cancer is the most common cancer in women in the United States after skin cancer, with one in three new cancers in females each year being breast cancer. The average lifetime risk for a woman developing breast cancer in the U.S. is around 13%. The five-year survival rates for localized, regional, and distant breast cancer are 99%, 86%, and 31% respectively, with an overall combined five-year survival rate of 91%. There are more than 4 million breast cancer survivors in the U.S., and research suggests that 25% to 30% will experience recurrence. Weight gain is a known risk factor for breast cancer recurrence, highlighting the importance of maintaining a healthy weight for survivors.
Obesity is associated with an increased risk of cancer and cancer recurrence, particularly in estrogen-driven breast cancers. Adipose tissue metabolizes estrogens, leading to higher estrogen levels that can stimulate breast cancer growth. Fat tissue can also increase inflammation in the body, impairing natural cancer cell surveillance and promoting hormonal reactivity that can ultimately lead to an increased incidence of breast cancer. The American Cancer Society recommends breast cancer survivors reach and maintain a healthy weight, be physically active, and eat a healthy diet to reduce the risk of recurrence and improve quality of life.
Breast oncologist Dr. Louis Vandermolen emphasizes the importance of not feeling shame or guilt about weight gain after breast cancer treatment, as it is common and not something to be ashamed of. Survivors may face stress or different perspectives on life after undergoing treatment for a life-threatening illness like cancer, leading to changes in behavior around food and lifestyle choices. Women should focus on overall health and well-being rather than fixating on weight gain, as it is just one of many potential side effects of cancer treatment.
Reaching and maintaining a healthy weight can improve physical functioning, quality of life, and overall health for breast cancer survivors. Losing weight can also reduce the risk of developing other cancers and chronic diseases. Identifying factors that contribute to weight gain after breast cancer treatment early on could help healthcare providers intervene and support survivors in preventing excess weight gain. The ultimate goal is to promote a healthy longevity in breast cancer survivors by addressing modifiable risk factors like weight gain and its impact on cancer recurrence and cardiovascular disease risk.
