A Phase 2 interventional study of Biospecimen Collection and Informational Intervention in Localized Prostate Carcinoma, Locally Advanced Cervical Carcinoma and Locally Advanced Rectal Carcinoma, sponsored by City of Hope Medical Center. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-13.
Sponsored by City of Hope Medical Center · Phase 2, Interventional, and Supportive care
This phase II trial studies how well time-restricted eating works in reducing side effects of radiation or chemoradiation side effects when compared to nutritional counseling among patients with prostate, cervical, and rectal cancers. Time-restricted eating, also called short term fasting or intermittent fasting, is an eating plan that alternates between not eating food (fasting) and non-fasting periods. Nutritional counseling involves being asked to follow a healthy, balanced diet that includes instructions on what kinds of food are better tolerated during radiation and chemoradiation therapy. This trial may help researchers determine if certain diets may improve the anti-cancer effects of radiation therapy and reduce the side-effects of this treatment. If successful, these diets may be integrated into the future treatment of prostate, cervical, and rectal cancers.
PRIMARY OBJECTIVES:
I. To test the hypothesis that time-restricted eating during radiation therapy (RT) or chemotherapy and radiation therapy (chemoRT) could reduce the level of accumulated double stranded deoxyribonucleic acid (dsDNA) damage in peripheral blood mononuclear cells (PBMCs) over the course of RT as measured by the gH2ax assay.
II. To examine if time-restricted eating during RT is associated with reduced toxicity as measured by clinician reported adverse events using Common Terminology Criteria for Adverse Events (CTCAE) version (v)5.0, improved patient quality of life as measured by European Organization for the Research and Treatment of Cancer Quality of Life (EORTC-PR25) (prostate cancer) and EORTC-CR29 (rectal cancer), reduced dsDNA damage as measured by assay for 8-oxo-dG and persistent DNA damage in shed epithelial cells from the urinary tract, reduced oxidative DNA damage as measured by reduced cumulative 8-oxoguanine DNA adducts, impacts the diversity of microbiome in relation and development of radiation induced microbiota dysbiosis and metabolic impact using liquid chromatography mass spectrometry (LC/MS) metabolomic analysis and correlative serological markers including IGF-1.0).
OUTLINE: Patients are randomized to 1 of 2 arms.
ARM I: Patients undergo time-restricted eating Monday through Friday only of each week on study during standard RT or chemoRT. Patients also undergo collection of blood throughout the trial.
ARM II: Patients receive nutritional counseling on study. Patients also undergo collection of blood throughout the trial.
6,370 studies on the registry are indexed under Prostatic Neoplasms; 1,400 are open to participants now.
This study's enrollment of 49 is below the median of 58 across 4,822 interventional studies indexed under Prostatic Neoplasms.
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Exclusion Criteria:
Patients undergo time-restricted eating Monday through Friday only of each week on study during standard RT or chemoRT. Patients also undergo collection of blood throughout the trial.
Procedure: Biospecimen Collection · Other: Quality-of-Life Assessment · Other: Questionnaire Administration · Behavioral: Short-Term Fasting
Patients receive nutritional counseling on study. Patients also undergo collection of blood throughout the trial.
Procedure: Biospecimen Collection · Other: Informational Intervention · Other: Quality-of-Life Assessment · Other: Questionnaire Administration
Undergo collection of blood
Also known as: Biological Sample Collection, Biospecimen Collected, Specimen Collection
Receive nutritional counseling
Ancillary studies
Also known as: Quality of Life Assessment
Ancillary studies
Undergo time-restricted eating
Also known as: Intermittent Fasting, Short-term Intermittent Fasting
Cumulative double strand deoxyribonucleic acid (dsDNA) damage of normal tissue
Will be measured by the gH2ax assay. The study population will be described by, and randomized groups compared with respect to baseline characteristics including demographics (age, race/ethnicity, education, gender for rectal cancer), clinical characteristics (prostate: pre-treatment prostate-specific antigen \[PSA\], National Comprehensive Cancer Network \[NCCN\] staging and rectal: American Joint Committee on Cancer version 8 \[AJCC8\] staging), and metabolic features (diabetes, HbA1c, waist circumference, fat mass, lipids). Given the potential for differential outcomes among diabetics, the analysis of trial outcomes will also include diabetes as a covariate.
Time frame: Up to 1 year after radiation therapy/chemotherapy and radiation therapy (chemoRT)
Percentage of patients completing 4 weeks of time-restricted eating during RT
Feasibility and tolerability is pre-determined to be met if least 70% of patients randomized to time-restricted eating can complete at 4 weeks of time-restricted eating during their radiation course. Will be assessed through quarterly assessments of missing data points. The study dietician will track and report on compliance in the intervention (time-restricted eating) arm, and research coordinator will track and report accrual, screen failures, self-reporting survey completions and data entry metrics. Trouble areas will be discussed, and protocol amendments developed accordingly. The co-principal investigators (PIs) will review and determine whether feasibility of analysis is impacted and whether corrective measures can be implemented to improve data completeness.
Time frame: Up to 4 weeks
Rates of objective clinical adverse events (AEs)
Will assess acute (during and at 4 weeks after treatment) and long term (at 3 or 6 months). Will use repeated measures analysis of variance (ANOVA) accounting for within-between interactions. Will also perform simple paired t-tests to evaluated differences in toxicity observed by clinicians at the two final post-RT time points to evaluate if there is a trend towards clinical benefit associated with fasting.
Time frame: Up to 6 months
Quality of life (QoL) indices - PR25
Will be measured by previously validated instruments for QoL studies in prostate and rectal cancer patients, European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire - Prostate (EORTC-QLQ-PR25) during and after treatment. AEs will be clinician collected during study visits while QoL surveys will be collected from patients directly through automated electronic surveys. Will use repeated measures ANOVA accounting for within-between interactions.
Time frame: Up to 1 year after completion of RT/chemoRT
Quality of life (QoL) indices - CR29
Will be measured by previously validated instruments for QoL studies in prostate and rectal cancer patients, European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire - Prostate EORTC-QLQ-Colorectal (CR29) during and after treatment. AEs will be clinician collected during study visits while QoL surveys will be collected from patients directly through automated electronic surveys. Will use repeated measures ANOVA accounting for within-between interactions.
Time frame: Up to 1 year after completion of RT/chemoRT
Accumulated gH2ax foci
Will represent persistent damage in shed epithelial cells from the urinary tract and peripheral blood mononuclear cells (PBMCs) by flow cytometry. Will use repeated measures ANOVA accounting for within-between interactions.
Time frame: Up to 1 year after completion of RT/chemoRT
Oxidative DNA damage
Will be measured by reduced cumulative 8-oxoguanine DNA adducts. Will use repeated measures ANOVA accounting for within-between interactions.
Time frame: Up to 1 year after completion of RT/chemoRT
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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City of Hope Medical Center