Online Adaptive Radiation Therapy for Rectal Cancer

Study Overview
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Brief Summary
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In the present study, the investigators will evaluate the efficacy, toxicities, and of online adaptive radiation therapy (ART) for patients with rectal cancer treated with neoadjuvant chemoradiotherapy.

Official Title
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A Prospective Study to Evaluate Online Adaptive Radiotherapy in Rectal Cancer

Conditions
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Rectal Cancer

Intervention / Treatment
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* Radiation: Online adaptive radiation therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≥18 years old; Diagnose with rectal cancer; T3-T4 or N+, and no distant metastasis Neoadjuvant chemoradiotherapy intended; Surgery is expected after neoadjuvant therapy; ECOG score 0-2, expected to lie in the treatment bed for at least half an hour; Exclusion Criteria: With contraindications to rectal MRI; Received surgery, radiotherapy or chemotherapy for rectal cancer; History of pelvic radiotherapy.

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: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Online adaptive radiation therapy<br>Patients receive adaptive radiotherapy therapy and concurrent chemotherapy. | Radiation: Online adaptive radiation therapy<br>* A dose of 45Gy will be delivered to planning target volume (PTV)<br>* Other names: ART;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute toxicities(CTCA | evaluated with Common Terminology Criteria for Adverse Events (CTCAE) 5.0 | 3 months for the start of treatment | 
| Response rate after surgery | Clinical and pathological complete response and partial response rate after chemoradiotherapy | 3 monsh after treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Chronic toxicity | evaluated with Radiation Therapy Oncology Group (RTOG)/EORTC late radiation morbidity scoring scheme | 2 years after treatment | 
| Dose coverage of target volume (assessed by planing target volume V100%) | Planing target volume V100%, defined as the planing target volume receiving at least 100% of the prescribed dose (V100%), is used to evaluate the dose coverage of target volume. | Through study completion, an average of five month | 
| Margins for clinical target volume(CTV) and gross tumor volume (GTV) | Margins needed in online ART for CTV to planning clinical target volume (PCTV) and GTV to planning gross tumor volume (PGTV) to cover inter/intra-fraction motion | Through study completion, an average of five month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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rectal cancer, adaptive radiation therapy