Seeing cachexia clearly: the evolution of body composition and radiological biomarkers in cancer wasting

Cancer cachexia is a highly prevalent multifactorial syndrome with huge prognostic influence. It is primarily characterised by progressive tissue wasting and imaging can be a powerful tool for noninvasive, longitudinal assessment.

Ongoing exploration and development of imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI), as well as emerging radiological biomarkers, will deepen our understanding of distinct cachexia phenotypes.

Bioelectrical impedance (BIA) and dual-energy X-ray absorptiometry (DEXA) were amongst the earlier modalities used to assess body composition. They are accessible and easy to use; however, concerns remain regarding their accuracy, and a paucity of detail provided in their estimates. CT provides more granular muscle and adipose tissue measurements, and analyses can be augmented with the use of automated segregation systems and multislice volumetric analysis. This could be key for supporting its integration in clinical practice. Beyond conventional quantitative assessments, MRI may aid in characterising emerging, clinically important markers of cachexia such as muscle inflammation, fat infiltration or fibrosis. Positron emission tomography (PET) CT may also become important tools for exploring how specific tissue-level pathophysiology can be accurately detected.