An observational study in Stomach Neoplasms, Gastric Cancer (Diagnosis) and Gastric Adenocarcinoma, sponsored by Hainan General Hospital. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-28.
Sponsored by Hainan General Hospital · Observational
The purpose of this observational study is to learn how stomach cancer that has spread to nearby lymph nodes responds to standard chemotherapy combined with immunotherapy given before surgery. In people with locally advanced gastric cancer, this pre-surgery treatment can shrink the tumor and clear cancer cells from some lymph nodes. However, it is not clear which groups of lymph nodes around the stomach still contain cancer cells after treatment. The study will also examine whether dense scarring (fibrosis) around the tumor is linked to a lower chance of cancer remaining in the lymph nodes. This information may help doctors in the future decide whether some lymph node groups can be safely left in place during surgery for people with severe scarring.
Participants in this study will receive standard pre-surgery treatment with SOX chemotherapy (S-1 plus oxaliplatin) and a PD-1 inhibitor for at least 2 cycles. After treatment, they will undergo standard gastrectomy with D2 lymph node dissection, which is the routine surgical removal of the main lymph node groups around the stomach. During surgery, the surgeon will record the degree of scarring and difficulty in separating the tissues. Lymph nodes will be collected and labeled by station so that each group can be examined separately. The study will then describe how often cancer is found in each lymph node station after treatment and explore whether scarring is related to cancer remaining in the nodes. The study will also track surgical outcomes and follow participants for up to 3 years to assess cancer recurrence and survival.
Approximately 103 participants will be enrolled. The study is expected to run from January 2027 through December 2029. Each participant will be followed for about 3 years after surgery, with clinic visits every 3 months for the first 2 years and every 6 months in the third year. This study does not assign participants to different treatments; all participants receive standard care, and the study only observes and records the results.
Background and Rationale Currently, the treatment of locally advanced gastric cancer (LAGC) has evolved into a multidisciplinary comprehensive treatment model combining surgery and perioperative systemic therapy. Neoadjuvant chemotherapy combined with immunotherapy (such as PD-1 inhibitors) has been proven to further improve the pathological complete response (pCR) rate of LAGC. However, after treatment with this regimen, the distribution patterns of lymph node metastasis in various perigastric stations and the characteristics of residual lesions remain unclear. Current guidelines still recommend standard D2 lymphadenectomy for resectable gastric cancer patients receiving neoadjuvant therapy. In addition, it has been observed in clinical practice that neoadjuvant chemo-immunotherapy significantly increases edema and fibrosis in the peritumoral tissue. These changes in the local microenvironment cause the disappearance of anatomical planes and dense adhesions, which significantly increase surgical difficulty and risks. Currently, there is insufficient prospective evidence to answer whether the extent of lymphadenectomy can be safely reduced (omitting the dissection of specific stations) for patients with severe local tissue fibrosis after treatment.
Study Design and Interventions This is a prospective, multicenter, single-arm observational cohort study with a planned enrollment of 103 patients. The study will include patients with pathologically confirmed locally advanced gastric adenocarcinoma at clinical stage cT3-4aN+M0. All enrolled patients will receive standardized clinical routine neoadjuvant treatment, namely the SOX regimen (S-1 + oxaliplatin) combined with an anti-PD-1 inhibitor (including toripalimab, sintilimab, tislelizumab, or nivolumab), and complete at least 2 cycles of treatment. Following the completion of neoadjuvant therapy, patients will undergo standard distal or total D2 radical gastrectomy.
Imaging and Intraoperative Assessments Subjects will undergo standardized contrast-enhanced abdominal CT (or PET-CT as needed) assessments at baseline and at the end of neoadjuvant therapy (2-3 weeks pre-surgery). In addition to defining the treatment response of target lesions using the iRECIST criteria, the imaging evaluation will specifically record local microenvironment changes indicative of tissue edema and fibrosis, such as increased density, exudation, and stranding in the peritumoral space.
During the surgery, the primary surgeon will objectively assess the degree of edema, fibrosis, and dense adhesions in the peritumoral tissue, drainage areas, and roots of major blood vessels based on a semi-quantitative grading scale (grades 0 to 3). Researchers will quantitatively record the total operative time, dissection time, intraoperative blood loss, and whether any collateral damage occurs. After the specimen is extracted, the surgical team will immediately and strictly sort the perigastric lymph nodes (No. 1 to No. 16) station by station on the operating table. Each station will be independently marked, separately fixed, and sent for pathological examination. Mixed submission is strictly prohibited to ensure the accuracy of station-specific data.
Pathological Evaluation and Follow-up Pathologists, blinded to the patients' preoperative imaging results and clinical treatment information, will independently and accurately count and assess the residual metastasis status (ypN) of lymph nodes from stations No. 1 to No. 16. Furthermore, the study will record the incidence of complications within 30 and 90 days post-surgery and conduct a safety assessment using the Clavien-Dindo classification system. Long-term follow-up will be conducted within 1 to 3 years post-surgery to dynamically track the patients' disease-free survival (DFS) and overall survival (OS) through regular imaging and tumor marker reviews.
Interpretation and Limitations This study aims to answer questions that the overall ypN0 rate cannot address: the location of residual lesions after combined neoadjuvant chemo-immunotherapy, and whether the severity of peritumoral fibrosis carries information regarding this distribution. The study does not randomize participants to different extents of dissection, does not compare restricted dissection with standard D2 dissection, and does not provide a direct test of oncological non-inferiority for any restricted dissection strategy. Its value lies in generating prospective, station-resolved, and pathologically validated data that may indicate whether this strategy warrants formal evaluation, and in describing the relationship between treatment-induced fibrosis and surgical complexity. If the data show that residual lesions remain distributed across D1 and D2 stations regardless of the severity of fibrosis, the current standard of complete D2 dissection will be reinforced. If reproducible low-risk station profiles emerge in a definable subgroup, this finding will provide a rationale-but not evidence-for subsequent comparative studies.
3,399 studies on the registry are indexed under Stomach Neoplasms; 992 are open to participants now.
This study's planned enrollment of 103 is below the median of 278 across 790 observational studies indexed under Stomach Neoplasms.
Browse Stomach Neoplasms studies →This is the only study on the registry with Hainan General Hospital as lead sponsor.
Counted across the registry records on this site, refreshed daily.
The study population consists of adult patients (aged ≥ 18 years) with pathologically confirmed locally advanced gastric adenocarcinoma at clinical stage cT3-4aN+M0. These patients have successfully completed standardized clinical routine neoadjuvant therapy, specifically the SOX chemotherapy regimen combined with an anti-PD-1 immunotherapy, for at least two cycles. Following the completion of neoadjuvant treatment, they are scheduled to undergo, or have already undergone, a standard distal or total D2 radical gastrectomy at the participating medical centers.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
All enrolled participants receive standard neoadjuvant SOX chemotherapy combined with a PD-1 inhibitor for at least 2 cycles, followed by gastrectomy with D2 lymphadenectomy. No control group is assigned. Participants are observed prospectively from baseline through surgery and up to 3 years postoperatively.
Drug: Neoadjuvant SOX chemotherapy combined with PD-1 inhibitor
1\. Intervention Name: SOX regimen (S-1 and Oxaliplatin) Intervention Description: Patients will receive the standard SOX chemotherapy regimen, consisting of S-1 and oxaliplatin, as part of their neoadjuvant treatment. The treatment will be administered in clinical routine for a minimum of two cycles prior to surgery. 2. Intervention Name: Anti-PD-1 inhibitor Intervention Description: Patients will receive an anti-PD-1 inhibitor (which may include Toripalimab, Sintilimab, Tislelizumab, or Nivolumab) in combination with the SOX chemotherapy regimen as part of their neoadjuvant treatment. This immunotherapy will be administered for a minimum of two cycles prior to surgery. 3. Intervention Name: D2 radical gastrectomy Intervention Description: Following the completion of neoadjuvant therapy, patients will undergo a standard distal or total gastrectomy with D2 lymph node dissection. During the procedure, surgeons will objectively assess local tissue edema and fibrosis. Post-resection, t
This study also gives Nivolumab. No intervention listed here names it: that was found by reading the record.
Station-specific lymph node metastasis positivity rate after neoadjuvant chemoimmunotherapy
The primary outcome is the station-specific lymph node metastasis positivity rate after neoadjuvant chemoimmunotherapy, assessed by station-by-station pathologic examination of gastrectomy specimens. Each dissected nodal station (No. 1-No. 16, as applicable) is evaluated separately. For each station, the positivity rate is defined as the number of evaluable participants with at least one pathologically confirmed positive lymph node at that station divided by the number of evaluable participants in whom that station was pathologically assessed. A positive node is defined as a lymph node containing viable tumor cells on hematoxylin and eosin staining. Pathologic assessment is performed blinded to preoperative imaging, iRECIST response, and clinical treatment information. The outcome is assessed at postoperative pathology after D2 gastrectomy.
Time frame: Up to 2 weeks
Degree of Peritumoral Edema and Fibrosis
To evaluate the extent of peritumoral tissue edema, fibrosis, and dense adhesions during the surgical procedure. The primary surgeon will objectively assess these local microenvironment changes using a semi-quantitative grading scale ranging from Grade 0 (normal anatomical planes, no obvious adhesions) to Grade 3 ("frozen" extremely dense adhesions, anatomical planes completely disappeared). The study will also analyze the correlation between the degree of edema/fibrosis and surgical complexity metrics, such as total surgical time and intraoperative blood loss.
Time frame: Perioperative
No study locations are listed for this record.
Plan to share: Yes — De-identified individual participant data (IPD) underlying the results reported in this study, along with the study protocol and statistical analysis plan (SAP), will be shared. Data will be available beginning 6 months and ending 36 months following the publication of the primary research article. Access will be granted to qualified researchers who provide a methodologically sound proposal for achieving aims specified in the approved proposal, such as individual patient data meta-analysis. Proposals should be directed to the Principal Investigator via email. Data requestors will be required to sign a data access agreement and obtain appropriate ethical approval before data transfer.
Supporting information: Study protocol, Statistical analysis plan
Time frame: Beginning 6 months and ending 36 months following publication of the primary research article.
Access criteria: Access will be granted to qualified medical or academic researchers whose proposed use of the data has been approved by the Principal Investigator. Requestors must provide a methodologically sound research proposal, sign a formal data access agreement, and obtain appropriate ethical or Institutional Review Board (IRB) approval prior to receiving any de-identified data.
Start is estimated for Jan 2027; primary completion for Dec 2029, 35 months later.
Of 322 non-industry observational studies under Stomach Neoplasms, half reached primary completion within 57 months of starting (the median), counting those still running; a quarter within 29 and three quarters within 171. This study's planned 35 months is below that.
Counting every sponsor, half of 364 studies reached it within 54 months; a quarter within 29 and three quarters within 119.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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