An observational study in Gastrointestinal Cancers, Gastrointestinal Cancers - Stomach and Gastrointestinal Cancers - Colorectal, sponsored by Peking University Cancer Hospital & Institute. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-11.
Sponsored by Peking University Cancer Hospital & Institute · Observational
Purpose:
The purpose of this study is to evaluate the safety and efficacy of Non-Operative Management (NOM) and Organ Preservation First Strategy (OPFS) compared with Radical Operation (RO) in patients with deficient mismatch repair/microsatellite instability-high (dMMR/MSI-H) or POLE-mutated gastrointestinal cancers.
Background \& Design:
With the remarkable efficacy of neoadjuvant immunotherapy in dMMR/MSI-H or POLE-mutated gastrointestinal tumors, organ preservation has become a promising alternative to highly invasive surgeries. The NOR-MP trial is a single-center, bidirectional registry study consisting of two parts: a retrospective cohort study and a prospective observational registry.
Intervention Group (NOM/OPFS): Patients who achieve a clinical complete response (cCR) or near-cCR after neoadjuvant immunotherapy will undergo a "Watch \& Wait" (W\&W) strategy. Patients with near-cCR or non-cCR who are eligible for organ preservation will undergo local excision (LE) or endoscopic resection (including ESD or EMR).
Comparison Group (Radical Operation): Patients who undergo standard radical surgical resection after neoadjuvant immunotherapy.
The study aims to determine whether an organ-preserving approach can achieve comparable oncological outcomes and safety profiles while significantly improving patients' quality of life compared to radical surgery.
The NOR-MP trial is a single-center, bidirectional registry study designed to compare the clinical outcomes of Organ Preservation First Strategy (OPFS) / Non-Operative Management (NOM) against standard Radical Operation (RO) for patients diagnosed with dMMR/MSI-H or POLE-mutated gastrointestinal cancers. The study is divided into two sequential parts based on the nature of data collection:
Part 1: Retrospective Cohort Study
This part retrospectively reviews the medical records of eligible patients with dMMR/MSI-H or POLE-mutated gastrointestinal cancers who previously completed neoadjuvant immunotherapy. Patients are allocated into two historical cohorts:
Experimental Cohort (NOM/OPFS): Patients who achieved cCR/near-cCR after neoadjuvant immunotherapy and entered the "Watch \& Wait" (W\&W) program, as well as those with near-cCR or non-cCR who underwent local excision (LE) or endoscopic resection (including Endoscopic Submucosal Dissection [ESD] or Endoscopic Mucosal Resection [EMR]).
Control Cohort (RO): Patients who underwent radical surgical operation after neoadjuvant immunotherapy. Pathological outcomes (including the proportions of ypCR, ypTisN0, and ypT1-2N0) and surgical safety data will be collected and analyzed.
Part 2: Prospective Registry Study
This part prospectively enrolls newly diagnosed patients with dMMR/MSI-H or POLE-mutated gastrointestinal cancers receiving neoadjuvant immunotherapy. Following treatment evaluation by the multi-disciplinary NOR-MP research team, patients are enrolled into two parallel observational tracks:
Experimental Cohort (NOM/OPFS): Patients eligible for and consenting to NOM or OPFS. This includes the W\&W strategy for those achieving cCR/near-cCR, and LE or endoscopic resection (ESD/EMR) for those with near-cCR or non-cCR.
Control Cohort (RO): Patients who proceed to standard radical operation. Pathological response distribution (proportions of ypCR, ypTisN0, ypT1-2N0, and ypT3+ diseases) and short-to-long-term surgical safety endpoints will be prospectively documented.
By comparing the retrospective and prospective cohorts, this study evaluates whether the omission of radical surgery is oncologically safe and preserves organ function without compromising long-term survival.
779 studies on the registry are indexed under Gastrointestinal Neoplasms; 231 are open to participants now.
This study's planned enrollment of 22 is below the median of 197 across 176 observational studies indexed under Gastrointestinal Neoplasms.
Browse Gastrointestinal Neoplasms studies →Peking University Cancer Hospital & Institute is the lead sponsor of 261 studies on the registry; 128 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The target population consists of adult patients diagnosed with primary gastrointestinal cancers (including but not limited to colorectal cancer, gastric cancer, and gastroesophageal junction cancer) that are histologically confirmed as deficient mismatch repair/microsatellite instability-high (dMMR/MSI-H) or harboring polymerase epsilon (POLE) exonuclease domain mutations. All enrolled patients must have received or are scheduled to receive neoadjuvant or conversion immunotherapy prior to definitive local tumor management strategy determination.
Exclusion Criteria:
Retrospective Cohort Study: Patients who achieved cCR/near-cCR after neoadjuvant immunotherapy and entered the "Watch \& Wait" (W\&W) program, as well as those with near-cCR or non-cCR who underwent local excision (LE) or endoscopic resection (including Endoscopic Submucosal Dissection \[ESD\] or Endoscopic Mucosal Resection \[EMR\]). Prospective Registry Study: Patients eligible for and consenting to NOM or OPFS. This includes the W\&W strategy for those achieving cCR/near-cCR, and LE or endoscopic resection (ESD/EMR) for those with near-cCR or non-cCR.
Other: NOM/OPFS
Retrospective Cohort Study: Patients who underwent radical surgical operation after neoadjuvant immunotherapy. Pathological outcomes (including the proportions of ypCR, ypTisN0, and ypT1-2N0) and surgical safety data will be collected and analyzed. Prospective Registry Study: Patients who proceed to standard radical operation. Pathological response distribution (proportions of ypCR, ypTisN0, ypT1-2N0, and ypT3+ diseases) and short-to-long-term surgical safety endpoints will be prospectively documented.
Patients eligible for and consenting to NOM or OPFS. This includes the W\&W strategy for those achieving cCR/near-cCR, and LE or endoscopic resection (ESD/EMR) for those with near-cCR or non-cCR.
Organ Preservation Rate (for OPFS/NOM group)
The percentage of patients in the NOM/OPFS group who successfully maintain their native organ without requiring radical surgical resection or permanent stoma.
Time frame: Up to 3 years after the completion of neoadjuvant immunotherapy.
Surgical Safety and Postoperative Complications
Incidence and severity of perioperative complications classified by the Clavien-Dindo classification. This compares the safety data among patients undergoing Radical Operation (RO), Local Excision (LE), or endoscopic resection (ESD/EMR).
Time frame: Within 30 days and 90 days post-surgery.
Pathological Response Distribution (for RO group)
Proportions of patients in the radical operation cohort achieving pathological complete response (ypCR), ypTisN0, ypT1-2N0, and ypT3+ diseases to characterize the pathological efficacy of neoadjuvant immunotherapy.
Time frame: At the time of radical surgery (typically within 4-12 weeks post-immunotherapy).
Local Regrowth / Recurrence Rate
Rate of tumor regrowth in patients undergoing the "Watch \& Wait" strategy, or local recurrence in patients undergoing local/endoscopic excision.
Time frame: Followed up at regular intervals (every 3-6 months) up to 3 years.
Overall Survival (OS)
Defined as the time from treatment initiation to death from any cause.
Time frame: Up to 5 years.
Disease-Free Survival (DFS) / Disease-Specific Survival (DSS)
To compare the long-term oncological efficacy between the NOM/OPFS group and the RO group. DFS is defined as the time from the start of neoadjuvant immunotherapy to the date of first documentation of disease recurrence (local, regional, or distant), progression, or death from any cause.
Time frame: From enrollment/treatment initiation up to 5 years.
No study locations are listed for this record.
Plan to share: No
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Peking University Cancer Hospital & Institute