Real-World Clinical Study for Malignant Tumor-Induced Cachexia

Inclusion Criteria: * Aged 18 years or older (including 18 years). * Malignant tumor confirmed by histology or cytology (both malignant solid tumors and malignant hematologic tumors are eligible for enrollment). * Meeting the Fearon diagnostic criteria for cachexia. * Life expectancy of ≥2 months (for the prospective cohort only). * Able to sign the informed consent form (waiver of informed consent for the retrospective cohort). Exclusion Criteria: Retrospective Cohort: * Missing gender information. * Missing date of birth or age information. * Lack of any treatment or follow-up information after the date of meeting the diagnostic criteria for cachexia. Prospective Cohort: (Patients with any of the following are not eligible for enrollment in this study) * Patients who are unable to receive any treatment for any reason. * Patients who cannot undergo at least one follow-up. * Patients whom the investigator deems unsuitable for participation in this study.