OA: Cachexia in cancer: what is in the definition?

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Introduction

 

Cancer cachexia is a multifactorial syndrome with a dramatic impact on patient's quality of life associated with poor responses to antitumour therapy and decreased survival.1–5 The prevalence of cancer cachexia is high: it is estimated to affect 50–80% of patients with cancer and accounts for up to 20% of deaths due to cancer in 2014.3 The main clinical feature of cachexia is involuntary progressive weight loss as a result of reduction of skeletal muscle mass (SMM) with or without depletion of adipose tissue. While starvation is also characterised by the same properties, it is not possible to reverse cachexia by means of conventional nutritional support.6 7 This is due to the complex underlying pathophysiology of cancer cachexia in response to the tumour–host interactions.

Conclusion

This study presents a correlation with prognosis in favour of Evans et al’ definition as a tool for cachexia diagnosis. This means that weight loss and BMI decline are both key factors in patients with cancer leading to cachexia but less decisive as stated by Fearon et al. Instead, extra factors gain importance in order to predict survival, such as chronic inflammation, anaemia, protein depletion, reduced food intake, fatigue, decreased muscle strength and lean tissue depletion.

 Summary box
 

What is already known about this subject?

▸	Cachexia is a multifactorial syndrome with involuntary progressive weight loss as a result of reduction of skeletal muscle mass with or without depletion of adipose tissue.
▸	Cancer cachexia is characterised by systemic inflammation and metabolic changes leading to progressive functional impairment.
▸	Sarcopenia as an index for cancer cachexia is a matter of debate.
▸	There is a lack of consensus on a definition, diagnostic criteria and classification of cancer cachexia

What are the new findings?

▸	Evidence-based results showing a substantial difference in the prediction of overall survival comparing the diagnostic guidelines according to Fearon et al2 with the diagnostic guidelines according to Evans et al.1
▸	Putting the focus on weight loss and sarcopenia over-rates the assignment of the diagnosis of cachexia resulting in survival rates with less prognostic value.
▸	Additional factors gaining importance in the diagnosis of cancer cachexia are: chronic inflammation, anaemia, protein depletion, anorexia and fatigue.
▸	Extra humoural factors should be a new point of interest in the further exploration of cachexia parameters. (Humoral factors are factors that are transported by the circulatory system, that is, in blood, and include: Humoral immunity factors in the immune system. Hormones in the endocrine system.)

How might it impact on clinical practice in the foreseeable future?

▸	Standardisation of the routine clinical practice for diagnosis of cancer cachexia would help in the identification of patients who are more at risk for the development of cachexia.
▸	In view of the current therapeutic approach, which targets the fundamental pathways involved in the pathogenesis of cancer cachexia, monitoring the humoural factors in daily practice would create the possibility to capture the diagnosis of cancer cachexia up close.