Prevalence, characteristics and health consequences of abnormal body composition phenotypes in patients with malignant disease

Abnormal body composition phenotypes, such as sarcopenia (depletion of muscle mass), obesity (excess adipose tissue) and the combination of the two, sarcopenic obesity, have emerged as important predictors of clinical outcomes in several disease states. However, the prevalence and clinical importance of these phenotypes in patients with malignant diseases has not been well characterized. The overall purpose of this research was to investigate abnormal body composition phenotypes among patients with cancer; and to determine the prevalence, characteristics and health consequences associated with these phenotypes. Body composition was measured using gold-standard methods such as dual energy X-ray absorptiometry (DXA) and computerized tomography (CT) imaging analysis. This research has shown that, in patients with cancer, body composition is extremely variable. Sarcopenia, obesity and sarcopenic obesity are syndromes of concern for these patients, and these conditions cannot be verified by use of body weight or body mass index (BMI) alone. This research was the first to demonstrate that abnormal body composition phenotypes such as sarcopenia and sarcopenic obesity were independently linked to increased prevalence of chemotherapy-related toxicity, poor functional status, shorter time to tumor progression and reduced survival in patients with malignant disease. Moreover, the use of CT analysis was raised as a gold standard method for body composition assessment in patients with cancer. Computerized tomography is almost ubiquitously available in the health records of cancer patients, providing a measure of body composition for potential use to predict clinical outcomes, and individualize chemotherapy dosing. In summary, the wide variability of muscle and adipose tissues among patients with cancer and its association with important clinical outcomes, demonstrates that body composition assessment is a tool for future cancer care.