Colorectal (Colon or Rectal) Cancer, Gastrointestinal Cancer, Stomach (Gastric) Cancer
Conditions
Keywords
dMMR/MSI-H, POLE-mutated
Brief summary
This is a single-center, bidirectional (retrospective and prospective) registry study aimed at evaluating the safety and efficacy of Non-Operative Management (NOM) and Organ-Preserving Functional Surgery (OPFS) in patients with mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) or POLE-mutated gastrointestinal (GI) cancers who received neoadjuvant immunotherapy.Patients achieving a clinical complete response (cCR) or near-cCR may undergo a "Watch & Wait" (W&W) strategy, while those with near-cCR or non-cCR ($\\le ymrT2N0$) may undergo local excision (LE) or endoscopic resection (ESD/EMR). Patients undergoing radical operation (RO) will serve as the control cohort to compare oncological outcomes and safety data.
Interventions
OTHERNOM
Patients achieving a clinical complete response (cCR) or near-cCR may undergo a "Watch \& Wait" (W\&W) strategy, while those with near-cCR or non-cCR (≤ymrT2N0) may undergo local excision (LE) or endoscopic resection (ESD/EMR).
OTHERRO
Patients undergoing radical operation (RO) will serve as the control cohort to compare oncological outcomes and safety data.
Sponsors
Peking University Cancer Hospital & Institute
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
1. Retrospective Cohort Inclusion Criteria * Pathologically confirmed gastrointestinal malignancy determined as MSI-H/dMMR or POLE mutation, and initially resectable. * Completed prior immunotherapy. * No evidence of distant metastasis. * Managed with W\&W, LE, endoscopic surgery, or radical operation after treatment. 2. Prospective Cohort Inclusion Criteria * Pathologically confirmed gastrointestinal malignancy determined as MSI-H/dMMR or POLE mutation, and initially resectable. * Eastern Cooperative Oncology Group (ECOG) performance status of 0-1. * Immunotherapy status: naive, currently receiving, or completed treatment, and evaluated by the PKUCH-NOMIC research group as cCR/near-cCR or Non-cCR (≤ ymrT2N0). * No evidence of distant metastasis. * Absence of emergencies requiring immediate surgery (e.g., hemorrhage, perforation, obstruction).
Exclusion criteria
* Recurrent gastrointestinal tumors.Initial presence of unresectable distant metastases. * Serum creatinine \> 1.5 times upper limit of normal (ULN). * History of pelvic radiation therapy.Inability to tolerate MRI examinations. * History of other malignancies within the past 5 years with a survival rate significantly lower than the historical rectal cancer survival data of this center (except adequately treated basal cell carcinoma, cutaneous squamous cell carcinoma, small renal cell carcinoma, breast cancer, and papillary thyroid carcinoma). * Arterial thromboembolic events within the past 6 months (e.g., angina, myocardial infarction, transient ischemic attack \[TIA\], cerebral vascular accident \[CVA\]). * Prior receipt of other types of investigational anti-tumor therapies. * Pregnant or lactating women. * Concomitant diseases or mental health conditions that may interfere with study participation.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Organ Preservation Rate | 3 years after the completion of neoadjuvant immunotherapy. | The proportion of patients successfully managed with NOM without the need for supplementary radical surgery, loss of organ function, or a permanent stoma (specifically for rectal cancer patients). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Surgical Safety and Postoperative Complications | 3 years after the completion of neoadjuvant immunotherapy. | Incidence and severity of perioperative complications classified by the Clavien-Dindo grading system, comparing RO, LE, and endoscopic resection (ESD/EMR). |
| Distribution of Pathological Response (RO Group Only) | At the time of radical surgery (typically 4-12 weeks post-immunotherapy). | Percentage of patients achieving ypCR, ypTisN0, ypT1-2N0, and ypT3+ in the radical surgery cohort to characterize pathological response after immunotherapy. |
| Local Regrowth Rate | Regular follow-up every 3-6 months for up to 3 years. | The proportion of patients experiencing local tumor regrowth in the W\&W group or after local/endoscopic excision. |
| Overall Survival (OS) | Up to 5 years. | Time from the start of treatment to death from any cause. |
| Disease-Free Survival (DFS) | Up to 5 years from enrollment/treatment initiation. | Time from the initiation of neoadjuvant immunotherapy to the first documentation of disease recurrence (local, regional, or distant), progression, or death from any cause, comparing the NOM/OPFS group with the RO group. |
Countries
China
Contacts
CONTACTLin Wang Prof., M.D.
CONTACTXiaokang Lei Dr., M.D.
Outcome results
None listed