The First-line Treatment of RCLM With RAS Mutation Was Local Short-course Radiotherapy (SCRT) + PD-1+ Standard Therapy

Study Overview
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Brief Summary
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To explore the efficacy and safety of radiotherapy followed by PD-1+ standard chemotherapy in the first-line treatment of initial unresectable rectal cancer liver metastases

Official Title
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The First-line Treatment of RCLM With RAS Mutation Was Local Short-course Radiotherapy (SCRT) + PD-1+ Standard Therapy

Conditions
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Rectal Cancer

Intervention / Treatment
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* Drug: PD-1
* Radiation: SCRT
* Drug: Bevacizumab
* Drug: Oxaliplatin
* Drug: Calcium folinate
* Drug: 5-fluorouracil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Histologically confirmed adenocarcinoma of the rectum； The clinical stage evaluated by MRI was T3-4 and/or N+ and M1a(only liver metastasis)； ECOG PS 0-2； CHild Pugh A； Estimated survival ≥3 months; Women of childbearing age should comply with contraceptive measures if pregnancy test is negative; Adequate organ and bone marrow functions, ecg, blood, biochemical and other basic tests are not contraindications of chemotherapy; Adherence to scheduled visits, treatment plans, laboratory tests, and other study procedures Willingness and ability. Exclusion Criteria: Pregnant or lactating women; No previous antitumor therapy； No previous liver local therapy； No contraception during the reproductive period; patients known to have a history of allergy to any study drug, similar drug or excipient; Patients with risk of massive gastrointestinal bleeding or gastrointestinal obstruction; Patients with a history of thromboembolism, except those caused by PICC; Patients with active infection; Other conditions that the investigator determines are not suitable for inclusion in the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: (SCRT) followed by PD-1+ standard therapy<br> | Drug: PD-1<br>* Participants will receive Tislelizumab, 200mg, intravenously over 30 - 60 minutes, day 1 of every 3 weeks<br>Radiation: SCRT<br>* Radiotherapy dose: 5×5 Gy<br>Drug: Bevacizumab<br>* Participants will receive bevacizumab，5mg/kg，intravenously over 60 - 90 minutes, day 1 of every 2 weeks<br>Drug: Oxaliplatin<br>* Participants will receive Oxaliplatin，85mg/m2，day1<br>Drug: Calcium folinate<br>* Participants will receive calcium folinate ，400mg/m2，day1<br>Drug: 5-fluorouracil<br>* Participants will receive 5-fluorouracil ，400mg/m2，day1<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| progression free survival | The length of time from enrollment until the time of progression of disease (PFS, progression-free survival). | up to 36 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| objective response rate | Clinical response of treatment according to RESIST v1.1 criteria (ORR, objective response rate). | every 3 months (up to 36 months） |