Node-Sparing Short-Course Radiation Combined With Capecitabine and PD-1/CTLA-4 for MSS Early Rectal Cancer

Summary

This is a single-arm, prospective, multicenter study evaluating a novel neoadjuvant treatment strategy for patients with early, mid-low rectal adenocarcinoma that is microsatellite stable (MSS). Instead of irradiating regional lymph nodes, we deliver short-course radiotherapy (25 Gy in 5 fractions) exclusively to the primary tumor ("lymph-node-sparing" approach), immediately followed by four 3-week cycles of capecitabine plus combined PD-1/CTLA-4 immune checkpoint inhibitors. Two weeks after completing chemo-immunotherapy, tumor response is assessed. Patients who achieve a clinical complete response may enter a "watch-and-wait" program; others will undergo local excision or total mesorectal excision (TME) as appropriate. The primary endpoint is the rate of complete response (clinical and pathological). Secondary endpoints include organ-preservation rate, 3-year local recurrence, 3-year disease-free and overall survival, toxicity, and quality-of-life measures. Results from a pilot study suggest that this regimen may substantially improve complete response rates while reducing radiation-related toxicity, potentially allowing more patients to avoid radical surgery and permanent stoma.

Eligibility

Inclusion Criteria:

1. Patients who have a strong willingness to preserve the anus and are willing to receive neoadjuvant therapy.
2. Male or Female aged 18-80.
3. Patients diagnosed with low rectal cancer within 7 cm from the lower edge of the tumor to the anal verge by pelvic MRI and rectal ultrasound, the clinical stage is cT2-3N0M0.
4. Histologically confirmed rectal adenocarcinoma; Genetic testing suggests MSI-L or MSS, or tumor biopsy immunohistochemistry reveals pMMR, that is, MSH1, MSH2, MSH6, and PMS2 are all positive.
5. Eastern Cooperative Oncology Group (ECOG) score 0-1.
6. No previous treatment (including anti-tumor therapy, immunotherapy or pelvic radiation).
7. Informed consent form signed.

Exclusion Criteria:

1. Patients with a previous history of malignant tumors besides rectal cancer.
2. Patients with distant metastases before enrollment.
3. Patients with metastatic regional or non-regional lymph nodes are assessed by MRI or CT.
4. Patients with obstruction, perforation, or bleeding that require emergency surgery.
5. Patients with severe concomitant diseases and estimated survival time ≤ 5 years.
6. Allergic to any component of the therapy.
7. Patients who received immunosuppressive or systemic hormone therapy for immunosuppressive purposes within 1 month prior to the initiation of therapy.
8. Contraindications to radiotherapy and chemotherapy.
9. Patients who have received any other experimental drug (including immunotherapy) or participated in another interventional clinical trial within 30 days before screening.
10. Factors leading to study termination, such as alcoholism, drug abuse, other serious illnesses (including psychiatric disorders) requiring combination therapy, and patients with severe laboratory abnormalities. Patients with congenital or acquired immune deficiency (such as HIV infection).
11. Vulnerable groups, including mentally ill, cognitively impaired, critically ill patients, minors, pregnant or lactating women, illiterate, etc.

    Other conditions that investigators consider not suitable for this study.
12. Patient not suitable for participating by other concerns of researchers.

Conditions2

Interventions2

Related trials

• A Clinical Study to Evaluate the Safety and Tolerability of AWT020 in Patients With Advanced Malignancies — Shanghai Junshi Bioscience Co., Ltd.
• A Clinical Trial Comparing Long-Course Versus Short-Course Radiotherapy Followed by Immunotherapy Combined With Total Neoadjuvant Therapy (TNT) to Long-Course Radiotherapy Followed by TNT in Locally Advanced Rectal Cancer — Tao Zhang
• A LM-302 Combination With Other Anti-Tumor Therapies Phase ll Study — LaNova Medicines Zhejiang Co., Ltd.
• A Phase 2 Study Evaluating the Safety and Efficacy of JS207 With or Without JS015 in Combination With Chemotherapy in Patients With Colorectal Cancer — Shanghai Junshi Bioscience Co., Ltd.
• A Phase 2 Study of SSGJ-707 in Metastatic Colorectal Cancer Patients — Sunshine Guojian Pharmaceutical (Shanghai) Co., Ltd.
• A Phase I/II Study of CS2009 in Participants With Advanced Solid Tumors — CStone Pharmaceuticals
• A Phase II Trial Comparing Immunotherapy Versus Capecitabine Maintenance After Chemo-chemoradiotherapy for High-risk Nasopharyngeal Carcinoma — Sun Yat-sen University
• A Phase III Study of YL201 in Recurrent or Metastatic Nasopharyngeal Carcinoma — MediLink Therapeutics (Suzhou) Co., Ltd.

Browse More Trials