Combination of CT and Ultrasound Radiomics Combined With Liquid Biopsy to Predict Neoadjuvant Chemotherapy Response in Patients With Locally Advanced Gastric Cancer

Inclusion criteria

• Capable of understanding the study and voluntarily signing the written informed consent form (ICF) prior to any study-specified research procedures.
• Aged ≥18 and ≤80 years old at the time of ICF signing.
• Pathologically confirmed locally advanced gastric cancer (LAGC, cT2NxM0-cT4NxM0) with clinical indications for neoadjuvant chemotherapy.
• Completion of gastrointestinal contrast-enhanced ultrasound and contrast-enhanced abdominal CT before neoadjuvant chemotherapy.
• Provision of peripheral blood samples before chemotherapy (for genetic and protein detection).
• Availability of postoperative pathological specimens for TRG grading after standardized neoadjuvant chemotherapy.
• Willing and able to comply with all study protocol requirements.

Exclusion criteria

• Diagnosis of non-primary gastric cancer.
• Incomplete imaging data, failure to collect peripheral blood samples, or substandard sample quality.
• Discontinued chemotherapy, modified treatment regimen, or lack of complete postoperative pathological assessment.
• Unavailable follow-up data precluding evaluation of chemotherapy response.
• Concurrent participation in another clinical trial; or any other conditions judged by investigators to warrant subject withdrawal, including severe comorbidities requiring simultaneous treatment (psychiatric disorders included), alcohol dependence, substance abuse, or familial/social factors that may compromise subject safety or treatment compliance.