Preoperative Short-course Radiation Followed by Envafolimab Plus CAPEOX for MSS Locally Advanced Rectal Adenocarcinoma: a Prospective, Multicenter, Randomized Controlled Study (PRECAM-R)
Short-course radiotherapy combined with immunotherapy may bring revolutionary changes to the preoperative neoadjuvant treatment mode for locally advanced rectal cancer.In view of the shortcomings of the current preoperative neoadjuvant treatment model for locally advanced rectal cancer, we will explore the feasibility of a new model of short-course radiotherapy combined with immunotherapy, and develop a possible optimal plan based on the existing theoretical basis, namely short-course radiotherapy + PD-L1 monoclonal antibody combined with CAPEOX chemotherapy for 2 cycles, and explore the efficacy and adverse effects of this model. The study will also attempt to explore the characteristics of the treatment beneficiary population, explore the characteristics of the treatment beneficiary population by multi-dimensional tumor and microenvironmental information through multi-omics sequencing analysis, attempt to build an efficacy prediction model, early screening of the treatment beneficiary population for precise treatment, and thus explore a new model of radiotherapy combined with immunotherapy.
• Patients who are willing to receive neoadjuvant therapy.
• ≧18 years old.
• Diagnosed by digital rectal examination, colonoscopy, and high-resolution MRI of the pelvis, the tumor is less than or equal to 12 cm from the anus.
• Histologically diagnosed as rectal adenocarcinoma.
• The clinical staging by pelvic contrast-enhanced CT and pelvic high-resolution MRI were cT2-4a N+, cT3/T4a N0.
• MMR protein detection or MSI gene detection of rectal cancer specimens confirmed pMMR or MSS before treatment .
• The patient has good compliance and can come to the hospital for re-examination as required.
• ECOG Scale of Performance Status score 0-1 point.
• Have not received anti-tumor and immunotherapy before enrollment.
⁃ Laboratory inspections must meet the following standards:
‣ White blood cell count\>3.5×109/L, absolute value of neutrophils\>1.8×109/L, platelet count ≥75×109/L, hemoglobin ≥100g/L;
∙ INR≤1.5, and APTT≤1.5 times the upper limit of normal or partial prothrombin time (PT) ≤1.5 times the upper limit of normal;
• Total bilirubin ≤ 1.25 times the upper limit of normal; ALT and AST \< 5 times the upper limit of normal;
⁃ 24h creatinine clearance \>50mL/min or serum creatinine \<1.5 times the upper limit of normal.
⁃ Voluntarily participate in this study and sign the informed consent.