Research by scientists at the New York University College of Nursing emphasizes the importance to breast cancer patients of maintaining a healthy weight after surgery as a way of avoiding a complication known as lymphedema, or abnormal swelling in the limbs. The study, titled “Patterns of Obesity and Lymph Fluid Level during the First Year of Breast Cancer Treatment: A Prospective Study,” was published in the Journal of Personalized Medicine.
Obesity is known a risk factor for lymphedema, which is caused by obstructions in the lymphatic system that occur during breast cancer patients’ treatment. (The lymphatic system, part of the circulatory system, is composed of a series of vessels that carry a clear fluid called lymph.) Currently without any cure, lymphedema can be managed if addressed early but remains a serious problem for breast cancer survivors, impairing significantly patients’ quality of life.
Mei R. Fu, PhD, RN, associate professor of Chronic Disease Management at the college (NYUCN) and the study’s first author, said in a press release, “Obesity is an established risk factor not only for breast-cancer related lymphedema but also for breast cancer occurrence, recurrence, and fatality. Accordingly, we believe obesity is a significant, but modifiable, risk factor for lymphedema.”
However, studies disagree on the values of body mass index, a measure of obesity, thought to induce significant risk: some propose that a risk factor exists in patients with a BMI is of 30 kg/m2 or more (obese), while other studies defined it as a BMI of 25 kg/m2.
Researchers at NYUCN designed and performed a prospective study to investigate patterns of obesity and their relation to lymph fluid levels in the first year of cancer treatment. The research team enrolled 140 women and followed the participants over a period of one year after surgery, measuring patients’ weight, BMI, and percent of body fat together with lymph fluid level. Participants were instructed on the importance and on ways of maintaining pre-surgery weight.
They observed that among the participants that completed the study (136), approximately 60% of them were obese (30.8%) or overweight (32.4%); the rest (around 35%) were of normal weight. Weight patterns observed were largely maintained through follow-up, and after one year post-surgery the majority (72.1%) were at pre-surgery weight. Over the year, 15.4% had more than 5% of weight loss, and 12.5% had weight gain of more than 5%. The study results showed that lymphedema was particularly prevalent in patients with a BMI of at least 30 kg/m2.
These results suggest that, “[g]eneral instructions on having nutrition-balanced and portion-appropriate diet and physical activities daily or weekly can be effective to maintain pre-surgery weight. Such general instructions may create less burden and stress to women when facing the diagnosis and treatment of breast cancer,” concluded Dr. Fu.