A Prospective Real-World Observational Study of Nanocrystalline Megestrol Acetate in Patients With Cancer Cachexia

Inclusion Criteria: * Patients with histologically and/or cytologically confirmed malignancy. * Age ≥18 years at enrollment. * Eastern Cooperative Oncology Group (ECOG) performance status score of 0-2 and an expected survival of ≥3 months. * Meeting the diagnostic criteria for cachexia (based on Fearon's criteria). * Body mass index (BMI) ≤30. Exclusion Criteria: * Presence of any condition affecting gastrointestinal absorption, such as dysphagia, malabsorption, or uncontrolled vomiting; patients receiving tube feeding or parenteral nutrition. * Presence of anorexia due to anorexia nervosa, psychiatric disorders, or pain that makes eating difficult. * Patients with acquired immunodeficiency syndrome (AIDS). * Currently receiving or planning to receive other medications that increase appetite or body weight, such as corticosteroids (except short-term dexamethasone during chemotherapy), androgens, progestins, thalidomide, olanzapine, anamorelin, or other appetite stimulants. * Patients with Cushing's syndrome, adrenal or pituitary insufficiency, or poorly controlled diabetes mellitus.