Molecular Determinants Affecting Fluoro-L-thymidine (FLT) Positron Emission Tomography (PET) in Rectal Cancer

Study Overview
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Brief Summary
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The purpose of this study is to determine if positron emission tomography (PET) imaging with an imaging agent called 18F-fluorodeoxythymidine([18F]-FLT) will allow investigators to measure how well tumor(s) respond to treatment without taking a tissue sample (biopsy). Additionally, the investigators want to determine if it is possible to predict how well tumor(s) might respond to treatment with [18F]-FLT PET imaging.

Official Title
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Molecular Determinants Affecting Fluoro-L-thymidine (FLT) Positron Emission Tomography (PET) in Rectal Cancer

Conditions
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Rectal Cancer

Intervention / Treatment
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* Device: PET imaging with [18F]-FLT
* Drug: [18F]-fluorodeoxythymidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects with known rectal cancer. Subjects must have signed an approved consent form. Subjects must be 18 years of age or older. Exclusion Criteria: Children less than 18 are excluded. Pregnant women and women who are breast feeding will be excluded from this study. A serum beta HCG will also be performed for each pre-menopausal female subject. Patients who are acutely ill who are deemed by their treating physician as not suitable candidates for this study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: [18F]-FLT PET scans<br> | Device: PET imaging with [18F]-FLT<br>* Up to three [18F]-FLT PET scans; one before beginning treatment, one at week three of treatment, and one at week 11, after completion of treatment but prior to surgery.<br>Drug: [18F]-fluorodeoxythymidine<br>* [18F]-fluorodeoxythymidine is administered intravenously approximately 60 minutes prior to the start of PET image acquisition.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Utility of [18F]-FLT PET to assess cellular proliferation in neoadjuvant trials of patients with rectal cancer | Ability of this imaging technique to determine growth of cancer cells and as a quantitative biomarker of response to relevant, molecularly targeted, therapies | at study entry, at week 3 during chemotherapy and radiation, and at week 11 after treatment but before surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlative biology | Pre-treatment and intra-treatment rectal biopsy tissue and tissue from the post-treatment surgical tumor resection will be examined for cyclin D1, TK1, PCNA, pHis-H3, thymidylate, p-Erk, p-Akt to identify changes from pre-treatment to post-treatment | at study entry before treatment, at week 3 of treatment, and at week 11 after treatment |