Does nutrition support during chemotherapy increase long-term survival of cancer patients? Lessons from the past and future perspectives.

PURPOSE: The aim of this review was to analyze the potential effect of the nutritional support (oral supplementation/counseling, tube feeding, parenteral nutrition) combined with chemotherapy on long-term survival of cancer patients.
METHODS: Using various electronic databases, we retrieved all English language papers on the combination nutritional support and chemotherapy and including data on long-term survival.
RESULTS: 29 trials (4 non-RCT) were retrieved. No significant benefit was observed except for a longer survival in a few selected subgroups of patients, depending on the tumor stage and compliance with the nutritional support. However, no study included survival as primary endpoint or was adequately powered for this purpose, and patients were seldom affected by malnutrition, a condition which would have made them extremely vulnerable and unsafe during an intensive chemotherapy with significant gastrointestinal toxicity. Finally, nutritional regimens were often inappropriate as regards quality and quantity of nutrients or too similar in the two arms of the trial to expect a result.
CONCLUSION: From the review of these trials, it appears clear that there is absence of evidence more than evidence of absence of effect of the supplemental nutritional support. This poor scenario should not discourage future large multicenter trials to assess the potential of an early versus a delayed support in mildly malnourished patients. From the practical point of view, a nutritional supplementation should be considered when severe malnutrition caused by the disease or following repeated oncologic treatments can make the patients poorly compliant with further chemotherapy cycles, as recommended by the international guidelines.