Panels of experts have agreed on the definition of cancer cachexia stages (CCS). We evaluated the clinical relevance of these stages and proposed ways to apply the CCSs to the clinical practice via standardized methods. The CCS were applied to 207 patients with advanced non-small-cell lung or gastrointestinal cancers from the Human Cancer Cachexia Database via consensus among the coauthors. Patients were categorized as noncachectic, precachectic, cachectic, and in refractory cachexia. Through analysis of variance, χ2, and Kaplan-Meier analyses, we tested the relationships between CCSs and selected outcomes. The CCS were significantly correlated (P < 0.05) with patient-centered indicators, including overall symptom burden, quality of life, tolerability to chemotherapy, body composition, hospital stay, and survival. However, precachectic and cachectic patients behaved similarly in all these outcomes but were significantly different from noncachectic and refractory cachectic patients. The average scores for the abridged Patient-Generated Subjective Global Assessment (aPG-SGA) corresponded well with the CCSs and reflected nicely the cut-off scores recommended for the nutritional triage of cancer patients. In addition to the aPG-SGA, we proposed the Edmonton Symptom Assessment System and routine laboratory tests for the triage of patients with refractory cachexia, for whom comfort care is the primary goal. The cachexia clinic hosted by the McGill Nutrition and Performance Laboratory offers a model for diagnosing more precisely the pathophysiology and severity of precachectic and cachectic conditions. The cachexia clinic, by working closely with palliative care programs, may offer the best environment for a comprehensive and personalized approach to the nutritional and functional problems in advanced cancer patients.