Safety and Efficacy of Leucine-Restricted Diet Combined With Neoadjuvant Chemotherapy and Immunotherapy in Gastric Cancer

Consistent with previous literature, the investigators postulate that a leucine-restricted diet is safe and well-tolerated in gastric cancer patients receiving neoadjuvant chemo-immunotherapy. Furthermore, the investigators propose that this dietary regimen promotes the activation of immune cells within the tumor microenvironment (TME). When combined with neoadjuvant chemo-immunotherapy, it demonstrates synergistic anti-tumor efficacy, thereby improving patient prognosis.

Sex

All

Minimum age

18 Years

Maximum age

70 Years

Inclusion Criteria:

* Pathological Confirmation: Histologically confirmed locally advanced gastric cancer.
* Demographics: Aged 18 to 70 years, inclusive, regardless of gender.
* Dietary Capability: Capable of oral intake or receiving a liquid diet via nasogastric tube.
* Consent: Willing to participate in the study and have signed the Written Informed Consent Form (ICF).
* Staging and Treatment Indication: No evidence of distant metastasis on imaging examinations (such as CT or PET-CT), with a clinical stage of locally advanced gastric cancer, indicating the need for neoadjuvant chemo-immunotherapy prior to surgery.
* Exclusion of Other Malignancies: No concurrent primary malignant tumors other than gastric cancer.

Exclusion Criteria:

* Cognitive or Psychiatric Impairment: Cognitive dysfunction or psychiatric disorders severe enough to prevent the patient from understanding the study content or providing informed consent.
* Diabetes Mellitus: Diagnosis of Type 1 or Type 2 diabetes mellitus.
* Gastrointestinal Conditions: Presence of severe diarrhea, intractable vomiting, severe malabsorption syndrome, paralytic or mechanical intestinal obstruction, or active gastrointestinal bleeding.
* Allergy/Hypersensitivity: Known hypersensitivity or allergy to any of the main components of the leucine-deficient nutritional powder.
* Concomitant Supplements: Current use of other nutritional supplements that may potentially confound the study results or affect the evaluation of efficacy.
* Treatment Tolerance: Inability to tolerate neoadjuvant chemo-immunotherapy, or occurrence of severe gastrointestinal adverse events following such treatment.
* Pathological Diagnosis: Postoperative pathological diagnosis confirming non-primary gastric cancer (e.g., metastatic tumors from other origins).

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