This is a prospective, multicenter, observational study designed to validate the predictive accuracy of a pre-developed multimodal deep learning model. The model integrates preoperative contrast-enhanced CT scans, digitized postoperative pathology images, and standard clinical data to estimate the risk of liver metastasis within two years after curative surgery in patients with stage I-III colorectal cancer.

The primary objective is to evaluate the model's performance in an independent, prospectively enrolled patient cohort. Participants will receive standard-of-care treatment according to clinical guidelines. The study involves no experimental interventions; it solely involves the collection and analysis of routinely generated clinical data. The goal is to assess the model's potential for clinical translation by providing a reliable tool for stratifying patients' risk of liver metastasis, which could inform personalized surveillance strategies.

Inclusion Criteria:

• Age 18-75 years, any gender.
• Clinical diagnosis of primary colon or rectal adenocarcinoma (Stage I-III). Scheduled to undergo curative radical resection for colorectal cancer.
• Preoperative contrast-enhanced abdominal/pelvic CT scan performed within 1 month before surgery, with acceptable image quality.
• No evidence of distant metastasis (including synchronous liver metastasis) on preoperative examination.
• ECOG Performance Status of 0 or 1.
• Patient or their legal representative voluntarily participates and provides written informed consent.

Exclusion Criteria:

• Postoperative pathological confirmation of non-primary colorectal adenocarcinoma or presence of distant metastasis.
• Intraoperative determination of non-R0 resection, or performance of palliative surgery/ostomy only.
• History of other malignant tumors.
• Previous history of liver surgery or liver transplantation.
• Death within the perioperative period (within 30 days after surgery).
• Refusal to participate in follow-up, withdrawal of informed consent, or loss to follow-up.

This study population consists of adult patients (aged 18-75) with newly diagnosed, stage I-III primary colorectal cancer who are scheduled to undergo curative resection at one of the participating clinical centers. This prospective cohort will be used for the independent validation of a pre-developed multimodal deep learning model designed to predict the risk of metachronous liver metastasis. All participants will provide informed consent prior to enrollment.