According to the results of a small open-label study published early online in the journal Cancer, fish oil supplementation may help patients to maintain their weight and muscle mass during chemotherapy for non-small cell lung cancer (NSCLC).

The authors note that involuntary weight loss is a major contributor to mortality and morbidity in patients with advanced cancer.  Although supplementation with >2g eicosapentaenoic acid (EPA) has previously been shown to stabilise weight loss, attenuate lean tissue wasting and increase survival in these patients, three Phase III studies failed to demonstrate a clear benefit with regard to body weight or lean tissue.  They note that patients receiving active treatment for cancer may represent an opportunity for more timely nutritional intervention – this study therefore focused on such patients and sought to determine whether EPA supplementation at this stage could prevent weight and muscle loss during chemotherapy.   

The study included patients with NSCLC who had not received chemotherapy, but had consented to first-line treatment with platinum doublet-based chemotherapy.   A total of 204 patients were initially screened and 41 recruited – the major reasons for exclusion were ineligibility for chemotherapy, participation in a clinical trial (nonstandard treatment), and <2 computed tomography (CT) images available. 

Patients received either standard of care (n=24) or fish oil (2.2g EPA/day; n=17), for the duration of their chemotherapy.  Patients were given the choice of taking the EPA as either capsules (four per day) or liquid, in an attempt to improve compliance.  One patient in the EPA group was unable to achieve >80% compliance and was therefore excluded from the analyses.  Skeletal muscle and adipose tissue were measured using CT images, and weight recorded at baseline and throughout chemotherapy.

The authors report that patients in the EPA group maintained their weight (0.5kg ± 1.0kg) whereas those receiving standard of care lost an average of 2.3 kg (± 0.9 kg)  by time their chemotherapy had ended (P<0.05).  Approximately 69% of patients in the EPA group gained or maintained muscle mass compared with 29% in the standard of care group.  No difference in total adipose tissue was observed between the two groups.

The authors note that their findings support those of earlier trials but that improvements in weight have been reported with chemotherapy, so the maintenance of weight and muscle cannot be solely attributed to the EPA intervention.  They acknowledge that the results require verification in larger randomised controlled trials.