Interventions for weight reduction in obesity to improve survival in women with endometrial cancer

BACKGROUND: Diagnoses of endometrial cancer are increasing secondary to the rising prevalence of obesity. Obesity plays an important role in promoting the development of endometrial cancer, by inducing a state of unopposed oestrogen excess, insulin resistance and inflammation. It also affects treatment, increasing the risk of surgical complications and the complexity of radiotherapy planning, and may additionally impact on subsequent survival. Weight-loss interventions have been associated with improvements in breast and colorectal cancer-specific survival as well as a reduction in the risk of cardiovascular disease, a frequent cause of death in endometrial cancer survivors. OBJECTIVES: To determine the impact of weight-loss interventions, in addition to standard management of endometrial cancer, on overall survival and the frequency of adverse events.Secondary objectives include an assessment of weight-loss interventions on endometrial cancer-specific survival, weight loss achieved, cardiovascular event frequency and quality of life both overall and stratified according to patient body mass index (BMI), where possible. SEARCH METHODS: This review searched Cochrane Central Register of Controlled Trials, MEDLINE, Embase and reference lists of articles, trial registries, and international gynaecological oncology conference abstracts from inception to January 2018. SELECTION CRITERIA: Randomised controlled trials (RCTs) of interventions to facilitate weight loss in overweight or obese women undergoing treatment for, or previously treated for, endometrial cancer were selected. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed trial quality, and extracted data with disagreements resolved by a third review author. Study authors were contacted to obtain missing data, including details of any adverse events. MAIN RESULTS: = 0%; very low-certainty evidence) when compared with usual care. No serious adverse events, for example hospitalisation or deaths, were reported in included trials. Lifestyle and behavioural interventions were associated with a higher risk of musculoskeletal symptoms (RR 19.03, 95% CI 1.17, 310.52, P = 0.04, two RCTs, 91 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: There is currently insufficient high-quality evidence to determine the effect of combined lifestyle and behavioural interventions on survival, quality of life, or significant weight loss in women with a history of endometrial cancer compared to those receiving usual care. The limited evidence suggests that there is little or no serious or life-threatening adverse effects due to these interventions, although musculoskeletal problems were increased, presumably due to increased activity levels. Our conclusion is based on low- and very low-quality evidence from a small number of trials and very few patients. We therefore have very little confidence in the evidence: the true effect of weight-loss interventions in obese women with endometrial cancer is currently not known.Further methodologically-rigorous, adequately-powered RCTs are required with follow-up of 5 to 10 years duration. These should focus on the effects of varying dietary modification regimens, pharmacological treatments associated with weight loss and bariatric surgery on survival, quality of life, weight loss and adverse events.