An interventional study of Time-restricted eating and Questionnaire Administration in Rectal Cancer Stage II, Rectal Cancer Stage III and Breast Cancer Stage I, sponsored by Fred Hutchinson Cancer Center. Recruiting at 1 site in United States. Open to participants aged 21 Years and older. Per ClinicalTrials.gov, last updated 2026-07-29.
Sponsored by Fred Hutchinson Cancer Center · Not applicable, Interventional, and Other
The goal of this clinical trial is to test meal-timing as a novel and sustainable interventional approach during cancer treatment to improve therapeutic response and metabolic health in an understudied population. This clinical trial will enroll patients with rectal or breast cancer receiving neoadjuvant treatment at the Alaska Native Medical Center (ANMC), which is part of the Alaska Native Tribal Health Consortium (ANTHC).
A promising strategy for improving the efficacy of anticancer treatments and reducing associated toxicities involves combining treatment with fasting regimens. In pre-clinical and clinical studies, various forms of fasting have been shown to induce tumor regression and improve long-term survival. According to the differential stress sensitization theory, fasting is thought to sensitize tumor cells to the cytotoxic effects of chemotherapy and radiation, while protecting healthy cells by increasing stress resistance. While healthy cells slow their growth and become more stress resistant in response to fasting, cancer cells cannot survive in nutrient-deficient environments; although the underlying mechanisms are not fully understood. However, extended water-only fasting can be challenging for patients and poses undue health risks. Intermittent fasting, and specifically time-restricted eating (TRE), may offer a viable alternative. TRE involves eating within a shorter window (e.g., 8 hours) and fasting for the remainder of the day but involves no other dietary restrictions. Because of its simplicity, TRE may be more sustainable than other fasting regimens. TRE also improves several cardio-metabolic endpoints, including insulin sensitivity, which may also be beneficial during anticancer treatments.
Participants will be randomized to one of two groups:
Participants are assigned to either TRE (8-hour daily eating period, starting 1-3 hours after waking up) or a control group defined as a ≥12-hour daily eating period. Their randomized meal assignment arm begins no later than 1-2 week after they begin cancer treatment and ends at end of treatment (resection if indicated). This is a period of approximately 6 months.
During this time, participants will be asked to record the time they started and finished eating every day. Electronic reminders and weekly calls to the participants will be made by study staff who maintain records of patient's meal timing. Researchers will time the TRE schedules relative to sleep time (not time of day), which is a reasonable proxy for circadian time. The control group was designed to mimic typical eating habits in the U.S., as data from NHANES suggest that the median American eats over a 12.5-hour period each day. Aside from these general prescriptions, no set number of snacks, meals, or calories will be prescribed. Instead, researchers will measure how TRE affects self-reported mealtimes, meal frequency, and food intake through a combination of daily adherence surveys, 3-day food records and continuous glucose monitoring (CGM).
Participants will receive weekly one-on-one nutrition counseling during the first month and then monthly counseling sessions thereafter. Participants will complete questionnaires at intake and subsequent follow-up assessments. Blood and stool samples will also be collected from participants throughout the study.
2,400 studies on the registry are indexed under Rectal Neoplasms; 587 are open to participants now.
This study's planned enrollment of 100 is above the median of 65 across 1,751 interventional studies indexed under Rectal Neoplasms.
Browse Rectal Neoplasms studies →Fred Hutchinson Cancer Center is the lead sponsor of 547 studies on the registry; 80 are open to participants now.
Of its 59 completed or terminated interventional studies of FDA-regulated products, 46 (78%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HER2
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants assigned to the TRE group will have an 8-hour daily eating period, starting 1-3 hours after waking up \[8 hours eating / 16 hours fasting per day (6+ days a week)\].
Behavioral: Time-restricted eating · Other: Questionnaire Administration · Procedure: Biospecimen Collection · Behavioral: Health coaching
Participants assigned to the control group are not time-restricted, and have a 12+ hour window of eating per day.
Other: Questionnaire Administration · Procedure: Biospecimen Collection · Behavioral: Health coaching
Participate in time-restricted eating plan
Complete questionnaire
Undergo collection of blood and stool
Receive nutrition counseling
Pathological Complete Response (pCR) rate
The pCR will be defined as an absence of residual invasive cancer on hematoxylin and eosin evaluation of the complete resected rectal or breast specimen and all sampled regional lymph nodes. It will be treated as a binary variable.
Time frame: At completion of neoadjuvant treatment (3-6 months)
Treatment-related toxicity
The Patient Reported Outcome-Common Terminology Criteria for Adverse Events (PRO-CTCAE v.5) measurement system will be used to measure treatment-related toxicities. The PRO-CTCAE will be administered on a weekly basis throughout the intervention and will calculate the average over all items for each time point. Surveys will be timed relative to the start of each oncologic treatment segment.
Time frame: From enrollment until completion of neoadjuvant or adjuvant treatment (3-8 months)
Treatment Delivery (RDI and Completion)
Chemotherapy, targeted therapy, immunotherapy and/or radiation data will be abstracted to calculate relative dose intensity (RDI--delivered ÷ planned dose intensity, mg/m²/week) for each drug, expressed continuously and dichotomized at ≥85%. Regimen-level RDI will be calculated as the average across drugs or based on the dose-limiting agent. We will also calculate the proportion of participants completing all planned cycles without unplanned reductions or delays.
Time frame: From enrollment until completion of neoadjuvant or adjuvant treatment (3-8 months)
Clinical Complete Response (cCR)
A cCR will be defined as the clinical absence of residual disease on physical examination, endoscopic examination, and/or repeat MRI imaging following completion of total neoadjuvant treatment.
Time frame: At completion of neoadjuvant treatment (3-6 months)
Tumor volume
Standard of care CT and MRI images will be obtained at the time of diagnosis for staging. A repeat standard of care MRI imaging may be obtained prior to surgery to assess response to neoadjuvant therapy and to guide clinical and surgical management. Researchers will obtain routine clinical restaging scans from participants and use them to estimate changes in tumor volume between the two time points.
Time frame: From baseline to surgery (3-6 months)
Objective response rate (ORR)
The ORR is defined as the percentage of people who have a partial response (defined as a decrease in tumor volume) or a complete response to treatment between enrollment and surgery.
Time frame: At the time of surgery following neoadjuvant treatment completion (3-6 months)
Neoadjuvant rectal (NAR) score
The NAR score is a validated surrogate endpoint for oncologic outcomes used in rectal cancer clinical trials. It takes as input the pathologic nodal status and the clinical and pathologic T-stage.
Time frame: At completion of neoadjuvant treatment for rectal cancer (3-6 months)
Provider-reported adverse events
As secondary measures of toxicity, researchers will collect provider-reported adverse event data. Researchers will analyze the incidence of grade 3-4 toxicities and calculate the aggregated Toxicity Index (TI). The TI accounts for the frequency and cumulative burden of all toxicities during the treatment period.
Time frame: From enrollment until completion of neoadjuvant or adjuvant treatment (3-8 months)
Health-related quality of life (HR-QOL)
We will use the widely-used and validated European Organization for Research and Treatment of Cancer Quality of Life (QOL) core questionnaire C30 (EORTC QLQ-C30), the colorectal-cancer specific questionnaire (EORTC CR29), and the breast cancer specific questionnaire (PR\_BR23). For this study, we focus on highly prevalent rectal and breast cancer treatment-related symptoms, including fatigue, insomnia, pain and bowel-related items (stool frequency, flatulence, and fecal incontinence).
Time frame: From enrollment until completion of neoadjuvant or adjuvant treatment (3-8 months)
Adherence
Adherence will be defined as at least 70% of the daily regimen followed (for example, eating \<8 hours for 6 or more days per week on average during the 6-month treatment period). Participants will be asked to self-report their adherence using a weekly survey, which asks participants to record the time they start and finish eating each day and to document any reasons for non-adherence.
Time frame: From enrollment until completion of study participation (3-8 months)
Progression-free survival (PFS)
Progression-free survival (PFS) is the length of time from randomization to disease progression or death from any cause.
Time frame: 12- and 24 months post completion of neoadjuvant treatment and surgery or adjuvant treatment.
Relapse-free survival (RFS)
Relapse-free survival (RFS) is the length of time after primary cancer treatment ends that a patient survives without any signs or symptoms of that cancer.
Time frame: 12- and 24 months post completion of neoadjuvant treatment and surgery or adjuvant treatment.
Overall survival (OS)
Overall survival (OS) is the time from randomization to death from any cause.
Time frame: 12- and 24 months post completion of neoadjuvant treatment and surgery or adjuvant treatment.
Plan to share: No
No publications or documents are linked to this record.
Started Jul 2026 (actual). Primary completion is estimated for Aug 2029, 37 months after the start.
Of 329 non-industry interventional studies with no phase under Rectal Neoplasms, half reached primary completion within 51 months of starting (the median), counting those still running; a quarter within 23 and three quarters within 78. This study's planned 37 months is below that.
Counting every sponsor, half of 336 studies reached it within 51 months; a quarter within 23 and three quarters within 78.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Fred Hutchinson Cancer Center →