Respiratory sarcopenia and prehabilitation in thoracic oncology: Diagnostic approaches and clinical implications.

Respiratory sarcopenia (RS) is increasingly considered in thoracic oncology because reduced strength and cough effectiveness may relate to perioperative pulmonary complications, symptom burden, and treatment tolerance. However, definitions, thresholds, and measurement protocols vary across studies, and the feasibility of bedside versus imaging-based approaches differs by setting. Evidence synthesizing RS-related measures remains heterogeneous, with observational data more common than prospective trials. In this review we aimed to summarize RS diagnostic approaches relevant to thoracic oncology, collate reported associations with perioperative and longitudinal outcomes in lung cancer, and outline pragmatic, evidence-aware prehabilitation and monitoring considerations for clinical practice. Strength-first screening with simple bedside tests, followed by selective confirmatory measures when resources allow, appears pragmatic for thoracic oncology pathways, while imaging and ultrasound measures may add context when available. Reported associations between RS-related metrics and outcomes in lung cancer are suggestive but not uniform, reflecting variability in cohorts, cutoffs, and protocols; thresholds require context-specific interpretation and, where possible, local validation. Within multidisciplinary care, RS-informed prehabilitation and monitoring may be considered to support risk assessment and clinical decision-making as higher-quality prospective evidence accumulates.