low rectal cancer r
Conditions
Interventions
Experimental group:The enrolled patients will receive 5*5Gy short-course radiotherapy, followed by 4 cycles of capecitabine plus oxaliplatin (CAPOX) and Sintilimab, finally receive the "wait and watch
Sponsors
The Sixth Affiliated Hospital of Sun Yat-sen University
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Age 18 years or older; 2. Pathologically confirmed rectal adenocarcinoma, with all other histological types excluded; 3. Mismatch repair protein (MMR) immunohistochemistry of rectal tumor biopsy specimens clearly identified as pMMR; 4. The lower edge of the rectal tumor lesion is =5 cm from the anal verge based on high-resolution pelvic MRI; 5. ECOG performance status score of 0-1; 6. High-resolution pelvic MRI assessment shows T2 or T3a/b (=5 mm) with N0, EMVI(-), LLN(-); T stage confirmed in combination with rectal ultrasound; 7. No prior systemic antitumor treatment for colorectal cancer, including cytotoxic drugs, immune checkpoint inhibitors, molecular targeted therapy, endocrine therapy, etc.; 8. Adequate organ function based on lab values obtained during the screening period: white blood cell count =3×10^9/L, neutrophil count =1.5×10^9/L, platelet count =75×10^9/L, total serum bilirubin =1.5× upper normal limit (UNL), AST or ALT =2.5×UNL, serum creatinine =1.5×UNL; 9. Female participants of childbearing potential must have a negative serum pregnancy test within 3 days prior to starting study medication and agree to use a medically approved highly effective method of contraception (e.g., intrauterine device, contraceptive pills, or condoms) during the study period and for 3 months after the last dose; male participants with partners of childbearing potential must be surgically sterile or agree to use effective contraception during the study and for 3 months after the last study drug dose; 10. Willing and able to comply with study protocols and visit schedules, and sign an informed consent form.
Exclusion criteria
Exclusion criteria: 1. Whole-body CT, MRI, or PET-CT (at least including the chest, entire abdomen, and pelvis) confirms distant metastasis (M1); 2. Patients with complete intestinal obstruction, active bleeding, or perforation requiring emergency surgery; 3. History of or concurrent active malignancy (except for malignancies previously treated with curative intent and disease-free for over 5 years, or in situ carcinomas that can be fully cured with adequate treatment); 4. Occurrence of thrombotic or embolic events within 12 months prior to study enrollment, such as cerebrovascular accidents (including transient ischemic attacks), pulmonary embolism, or deep vein thrombosis; 5. Occurrence within 12 months prior to study enrollment of: myocardial infarction, severe/unstable angina, heart failure of NYHA class 2 or higher, clinically significant supraventricular or ventricular arrhythmias, or symptomatic congestive heart failure; 6. Systemic use of antibiotics >=7 days within 4 weeks prior to study enrollment, or unexplained fever >38.5°C during screening/before first dose (fever due to tumor, as judged by the investigator, is allowed); 7. Major surgery or severe trauma (such as laparotomy, thoracotomy, or organ resection via laparoscopy) within 2 months prior to study enrollment (surgical incisions must be fully healed before enrollment); 8. Presence of interstitial lung disease, non-infectious pneumonia, uncontrolled systemic disease, or autoimmune disease; 9. Human immunodeficiency virus (HIV) infection or known acquired immunodeficiency syndrome (AIDS), untreated active hepatitis (hepatitis B, defined as HBV-DNA >=500 IU/ml; hepatitis C, defined as HCV-RNA above the detection limit of the assay) or co-infection with hepatitis B and C; 10. Known or suspected allergy to any study-related drugs; 11. History of inflammatory bowel disease or familial adenomatous polyposis; 12. Pregnant or breastfeeding women; 13. Known dihydropyrimidine dehydrogenase (DPD) deficiency; 14. Women of childbearing potential (last menstruation <2 years) or men with reproductive potential who do not use or refuse effective non-hormonal contraception; 15. Other serious physical or mental diseases or laboratory abnormalities that may increase the risk of participating in the study, interfere with study results, or are deemed by the investigator as unsuitable for participation.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The rate of clinical complete response and successful local resection (cCR+ypT0-1); | — |
Secondary
| Measure | Time frame |
|---|---|
| The 3-year organ preservation rate;Three-year disease-free survival;The 3-year local recurrence rate;surgery-related complications;Health-related quality of life; | — |
Countries
China
Contacts
Public ContactXiaosheng He
The Sixth Affiliated Hospital,Sun Yat-sen University
Outcome results
None listed