Does Posttreatment Weight Loss Equate to Improved Quality of Life Among Survivors of Breast Cancer?

What is the connection between health-related quality of life (HRQOL) and weight loss as a result of adjuvant treatment for stage 1-3 breast cancer among female patients considered obese (body mass index [BMI] >30 mg/m²)? An international team of investigators recently tried to answer this question, knowing the concurrent worldwide rises in cases of obesity and breast cancer among patients considered obese, and their results appeared recently in the journal The Breast.

“Obesity is now defined as a disease state, and the American Society of Clinical Oncology endorses weight gain prevention and weight loss facilitation for all obese cancer patients,” the authors said.

Using data on 993 women that they obtained from the CANcer TOxicities trial, a large, contemporary, prospective trial, they focused on a 5% weight gain or loss from baseline in the time between diagnosis and the period immediately following primary treatment. Weight and BMI were initially measured at diagnosis (baseline) visit. The mean weight was 89.4 kg (range, 61.0-153.0), and the mean BMI, 34.5 kg/m² (range, 30.0-59.0). Changes in HRQOL were assessed using the European Organisation for Research and Treatment of Cancer questionnaires QLQ-C30 and QLQ-BR23.

The mean (SD) patient age at diagnosis was 59.1 (10.5) years, the median (interquartile range [IQR]) time from diagnosis to post treatment was 10.5 (IQR, 7.8-12.5) months, and most (79.6%) had hormone receptor—positive, human epidermal growth factor receptor 2–negative disease and underwent partial surgery (75.1%). In addition, 91.6% underwent radiation and 53.6%, adjuvant chemotherapy.

At the end of the study period, most (67.3%) of the women had maintained their weight, 14.1% had gained at least 5% from their baseline measure, and 18.6% lost more than 5% of their baseline weight. The women in this final group tended to be older (50-64 years), postmenopausal, and never-smokers.

Overall, the patients who lost weight had reduced odds of severe pain compared with those who gained weight (odds ratio [OR], 0.51; 95% CI, 0.31-0.86; P = .011) or whose weight remained stable (OR, 0.62; 95% CI, 0.41-0.95; P = .029). In addition, the group that lost weight had smaller mean drops in their HRQOL scores on the following measures compared with the stable-weight and weight-gain groups:

• Physical function: Lost: —6.2 (range, –8.7 to –3.7) Stable: —6.9 (range, –8.2 to –5.5) Gain: —12.9 (range –16.5 to –9.3)
• Dyspnea: Lost: 3.2 (range, —1.0 to 7.3) Stable: 9.2 (range, 6.5-11.9) Gain: 18.9 (range, 12.3-25.6)
• Breast symptoms: Lost: 13.4 (range, 9.0-17.2) Stable: 18.0 (range, 15.7-20.3) Gain: 22.1 (range, 16.8-27.3)

“Beyond impaired well-being, posttreatment functional decline leads to loss of independence, worse social and cost-related outcomes, and possibly impairs cancer-specific outcomes, while increased symptom burden is associated with higher rates of nonadherence to adjuvant treatment and worse social rehabilitation in breast cancer survivors,” they concluded. “Our results inform further studies aimed at testing whether weight control can modulate some of these negative consequences.”

Going forward they suggest more intensive study of the effects of weight gain and loss in what they term the early survivorship period as a way “to mitigate many downstream sequelae of primary breast cancer treatment.”

Reference

Di Meglio A, Michiels S, Jones LW, et al. Changes in weight, physical and psychosocial patient-reported outcomes among obese women receiving treatment for early-stage breast cancer: a nationwide clinical study [published online April 11, 2020]. Breast. doi: 10.1016/j.breast.2020.04.02.