This is a randomized, double-blind, placebo-controlled, parallel-group, prospective, multi-center clinical trial, to evaluate the efficacy of silkworm pupa tablets in improving nutritional status and sarcopenia in patients with malignancies who have completed comprehensive treatment. All participants will be randomly assigned (1:1) to either experimental group (n=240): dietary advice + Wanshili Longbao Silkworm Pupa Tablets (main ingredients: freeze-dried active mulberry cocoon pupa powder, maltitol, milk mineral salt, mannitol, maltodextrin), 2 tablets three times daily before meals for 3 months, or control group (n=240): dietary advice + placebo (identical appearance), 2 tablets three times daily before meals for 3 months. The primary endpoint is sarcopenia prevalence at 3 months (based on AWGS 2019 criteria: muscle strength, muscle mass, and physical function).