Impact of weight loss after treatment on survival outcomes of overweight and obese patients with early­stage endometrial cancer.

Despite the fact that obesity is the main risk factor for endometrial cancer, there is limited evidence regarding the effects of body weight change on overweight and obese women treated for early-stage endometrial can its impact on cancer outcomes. A retrospective cohort study was performed including all overweight and obese patients with early-stage type-I endometrial cancer that were treated at the Insular University Hospital of Las Palmas (Las Palmas de Gran Canaria, Spain) between January 2007 and December 2019. Body weight change at 12 months of treatment was evaluated, as well as its impact on cancer outcomes. Weight loss ≥5% was independently evaluated regarding its impact on survival. A total of 526 women were studied, of which 152 (28.90%) were overweight (BMI ≥25 and <30) and 374 (71.10%) were obese (BMI ≥30). The median follow-up was 76.17 months, during which time 77 (14.64%) women died. In the survivor group, body weight at initial diagnosis was 86.4±17.9 kg compared with 84.6±16.4 kg 1 year after treatment, which corresponded to a significant mean weight loss of 1.47 kg (P<0.001). However, in the group of non-survivors, body weight at initial diagnosis was 84.7±15.7 kg compared with 84.7±14.6 kg 1 year after treatment, which demonstrated a non-significant mean weight loss of 0.63 kg (P=0.180). When comparing between the patients who maintained or gained ≥5% weight and those who lost ≥5% weight, there were no significant differences taking into account the whole cohort and follow-up time; however, when adjusting for the period between 32 and 98 months, survival was significantly higher in those patients that lost ≥5% of their initial body weight (P=0.025; log-rank test). Based on the final univariate and cer and multivariate analyses, body weight change at 12 months was not indicated to be a factor significantly affecting overall survival; adjusted hazard ratio was 1.01 (95% CI 0.97-1.05, P=0.723). In conclusion, even if greater weight loss is observed in patients with endometrial cancer that survive the disease, no significant impact on survival outcomes is observed based on multivariate analysis.