New cancer cachexia staging system for use in clinical practice.

OBJECTIVES

Previous attempts to classify cancer cachexia (CC) have demonstrated limitations regarding stages and diagnostic criteria. This study aims to develop and validate a new staging system for CC in patients with incurable cancer.

METHODS

This is an analysis of a database from a prospective cohort study of 1325 patients with advanced cancer referred for palliative care between 2016 and 2020. The cohort was randomly divided into two groups: Development (882 patients) and validation (443 patients) sets. A hierarchical cluster analysis was performed to distinguish different stages of CC in the development set. Next, the optimal cutoff points and ideal combinations of the most important factors associated with the CC groups (clusters) were ascertained. Finally, the relationship between the CC stages determined using the new system and body composition, quality of life, and overall survival was verified with the validation set.

RESULTS

The new system classified CC into three stages: Precachexia (10.8%), cachexia (57.8%), and refractory cachexia (31.4%), based on a combination of percentage weight loss in the past 6 mo (<15 or ≥15), body mass index (<21.0, 21.0-26.4, >26.4 kg/m2), and mid-upper-arm muscle area (≥38.0/≥35.5 or <38.0/<35.5 cm2 in men/women, respectively). The new staging system enabled a clear classification of patients into three CC groups according to the outcomes analyzed. Outcomes of patients with refractory cachexia were significantly worse than those in the other groups.

CONCLUSIONS

This study presents a useful, valid system for CC staging in the clinical setting, and is also capable of predicting outcomes, including quality of life and overall survival.