Fasting InTervention for Endometrial Cancer

Feasibility of recruitment will reported as the percentage of participants who consent to participate and meet eligibility criteria. Criterion for success: At least (≥) 50% of all eligible participants at Baseline (T0) consent to participate between both arms.

Feasibility of retention will be reported as the percentage of participants who adhere to and complete the prolonged overnight fasting (POF) intervention and data collection at all time points. Criterion for success: Greater than (>) 70% of all assigned participants complete the intervention and data collection at all time points (T2).

Acceptability will be reported as the percentage of participants who report satisfaction with the prolonged overnight fasting (POF) intervention after completion. Criterion for success: Greater than (>) 80% of all assigned participants report satisfaction with the intervention at the time of study completion (T2).

Change in metabolic biomarker levels (insulin, glucose, IGF-1, HbA1c) at post-surgery compared to pre-surgery, among participants in both the prolonged overnight fasting (POF) intervention and attention control groups. Blood specimens collected at baseline (T0), the day of surgery (T1) will be used to analyze changes in metabolic biomarker levels.

Fold change in concentration of blood and serum metabolomics (> 450 water-soluble metabolites and 600 lipid-related metabolites) at post-surgery compared to pre-surgery will be reported among participants in both the prolonged overnight fasting (POF) intervention and attention control groups. Blood specimens collected at baseline (T0), the day of surgery (T1) will be analyzed using Mass Spectrometry (MS) or Nuclear Magnetic Resonance (NMR). Fold Change (FC) represents the ratio of the average metabolite concentration at post-surgery compared to pre-surgery.

Change in participant quality of life in both the intervention and control groups as measured by scores on the Patient-Reported Outcomes Measurement Information System-29 (PROMIS-29) questionnaire will be reported. PROMIS-29 questionnaire is a 29-item validated measure with seven domains of health, including physical function, anxiety, depression, pain interference, fatigue, sleep disturbance, ability to participate in social roles and activities and pain intensity. Scores collected at baseline (T0) will be compared to scores collected the day of surgery (T1). Higher scores represent worse symptoms for symptom-oriented domains (anxiety, depression, fatigue, pain intensity, pain interference, and sleep disturbance) and better health outcomes for function-oriented domains (physical functioning and ability to participate in social roles and activities).

Change in participant quality of life in both the intervention and control groups as measured by the Rosenburg Self-Esteem Scale will be reported. The Rosenberg Self-Esteem Scale (RSES) is a 10-item self-report questionnaire measuring global self-worth and self-acceptance. It uses a 4-point Likert scale (strongly agree to strongly disagree), with scores ranging from 0-30 (or 10-40). Scores below 15 indicate low self-esteem. Scores collected at baseline (T0) will be compared to scores collected the day of surgery (T1).

Change in participant quality of life in both the intervention and control groups as measured by scores on the Hopwood's Body Image Scale will be reported. The Hopwood's Body Image Scale is a 10-item questionnaire used to measure affective, behavioral, and cognitive body image symptoms. Participants can indicate body image symptoms on a 4-point scale (0 "not at all" to 3 "very much"). The total score ranges from 0 to 30 and can be calculated by summing up the 10 items. A higher score means a higher level of body image disturbance. Scores collected at baseline (T0) will be compared to scores collected the day of surgery (T1).

Change in participant quality of life in both the intervention and control groups as measured by scores on the Pittsburgh Sleep Quality Index (PSQI) questionnaire will be reported. The PSQI is a self-administered questionnaire for evaluating subjective sleep quality. PSQI global scores range from 0 to 21, with higher scores indicating worse sleep quality. Scores collected at baseline (T0) will be compared to scores collected the day of surgery (T1).

Change in participant quality of life in both the intervention and control groups as measured by the Godin Leisure Time Exercise Questionnaire will be reported. The Godin Leisure Time Exercise Questionnaire assesses participants' frequency of leisure activity/exercise (strenuous, moderate or light) for more than 15 minutes during a 7-day period. Higher scores indicate a more active lifestyle. Scores collected at baseline (T0) will be compared to scores collected the day of surgery (T1).

Change in participant diet quality, in both the intervention and control groups, as measured by the Automated Self-Administered (ASA-24) dietary assessment questionnaire will be reported. The ASA-24 asks respondents about everything they ate and drank the previous day or in the last 24 hours. Responses collected at baseline (T0) will be compared to responses collected the day of surgery (T1).

Change in incidence of symptoms related to chemotoxicities and side effects from treatment among study participants on both arm as measured by scores on the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) questionnaire. The PRO-CTCAE was developed by the National Cancer Institute (NCI) to assess symptomatic adverse events (AEs) in adult patients receiving cancer therapy. The PRO-CTCAE is a self-administered questionnaire. Scores collected at baseline (T0) will be compared to scores collected the day of surgery (T1).