Cancer cachexia: Comparing diagnostic criteria in patients with incurable cancer

Cancer cachexia (CC) is a multifactorial syndrome that is associated with worse outcomes. Several criteria for its diagnosis have been suggested, but notable disparities exist. This study compared different diagnostic criteria for CC in patients with incurable cancer who are in palliative care.

A prospective cohort study was conducted at the National Cancer Institute in Brazil. Patients were classified by three CC diagnostic criteria, and comparisons between clinical, nutritional, and functional variables were verified according to the CC stage identified. Kaplan-Meier survival curves and Cox regression were used for the survival analysis. Concordance statistics were used to test the prognostic predictive accuracy of the criteria.

The prevalence of cachexia in the 1384 patients included in the study varied from 13.8% to 53.9% according to the classification criteria used. All criteria distinguished noncachectic patients from other categories according to the majority of the domains studied. However, the results were inconsistent in distinguishing patients with intermediate cachexia (mainly precachexia) from noncachectic and cachectic patients. Patients with cachexia or refractory cachexia faced a higher risk of 90-d mortality. The criteria described by Vigano et al. were found to be better at distinguishing the stages of CC regarding overall survival (hazard ratio increases according to CC severity: 1.87 to 2.87; concordance statistic: 0.74).

Our results demonstrate the disparities in existing CC diagnostic criteria and their inability to discriminate intermediate stages. Vigano et al.'s criteria is/was the most effective in predicting the prognosis. The development of new diagnostic criteria to improve CC classification requires future exploration.