Noninvasive Early Diagnosis of Colorectal Cancer Using Odor-Targeted Capture, Point-of-Care Testing, and Intelligent Analysis

Inclusion criteria

• Age 18 to 85 years, male or female
• Histopathologically or cytologically confirmed colon or rectal cancer (TNM stage I-IV) for colorectal cancer group
• Histopathologically confirmed adenomatous polyps, sessile serrated lesions, traditional serrated adenomas, or other precancerous lesions for precancerous lesion group
• No abnormality on colonoscopy within the past year; no personal history of colorectal cancer or other malignancies; no chronic diseases requiring long-term treatment for healthy control group
• Willing and able to provide signed informed consent

Exclusion criteria

• Hereditary colorectal cancer syndromes (e.g., familial adenomatous polyposis, hereditary non-polyposis colorectal cancer)
• Autoimmune diseases (e.g., systemic lupus erythematosus, rheumatoid arthritis)
• Severe cardiovascular, respiratory, or urinary system diseases
• Other primary malignant tumors
• Hematological diseases
• Unable to comply with study procedures (e.g., sample collection or questionnaires)
• Planning to become pregnant, pregnant, or breastfeeding
• Suspected or confirmed alcohol or drug abuse
• Known allergy to any drug used for colorectal cancer treatment
• Participation in another interventional drug clinical trial within the past month
• Any other condition that, in the investigator's judgment, makes the participant unsuitable for the study