Abstract:
Background
At least 40 - 80% of all cancer patients develop some degree of clinical
malnutrition and cachexia. The complex and multi-factorial nature of cancer
cachexia and the inability of conventional nutrition intervention to reverse or
attenuate the effects of this syndrome have driven investigators to consider
new therapies and approaches to manage the syndrome of cancer cachexia
including eicosapentaenoic acid (EPA), an n-3 fatty acid of fish oil origin.
Objectives
The aim of this study was to review Phase I, Phase II and Phase III (RCT)
trials investigating the safety and efficacy of n-3 supplementation in the
treatment of cancer cachexia in adult patients with unresectable solid
tumours, with special reference to weight loss, body composition, appetite,
dietary intake, energy expenditure, functional status, acute phase response
and quality of life. Adverse effects associated with EPA supplementation were
also reviewed.
Methodology and data collection
The major databases were systematically searched for studies that met the
inclusion criteria using a structured keyword search strategy or various
combinations of these keywords. Relevancy of studies was assessed by two
independent reviewers according to pre-determined inclusion and exclusion
criteria. Quality was assessed by two independent reviewers using the Jadad
scale. Data extraction was performed by the principal reviewer and one of the
independent reviewers, and investigators of the included studies were
contacted where further information was required. Meta-analysis was not
appropriate due to heterogeneity of the data. However, where possible, the
paired t-test was used for analysis of the data. Descriptive or non-quantitative
analysis of the tabulated data provided a summary of the characteristics of the
included studies enabling comparisons to be made between interventions and
outcomes within the specified population. Results
The search resulted in a total of 1408 citations, of which only 16 studies met
the inclusion and exclusion criteria. Of these, only 4 studies were of a good
quality. Although the reported data was incomplete and variable, the
combined analyses suggested that the effect of EPA supplementation on
weight, fat mass, dietary intake, energy expenditure, and acute phase
response was not significant. Interestingly there appeared to be a significant
increase increased or decreased? in lean body mass (p<0.05). There was
little or no data to draw any conclusions regarding the effect of
supplementation on appetite and quality of life.
Conclusion
Despite several limitations in this review, the data collected and analysed are
suggestive of the beneficial effects of EPA supplementation, but there remains
a significant lack of substantial evidence and conclusive statistical analysis to
confirm that EPA supplementation is a safe and effective method of
intervention in the management of patients with cancer cachexia.
