Ghoreishi, Z., Esfahani, A., Djazayeri, A., Djalali, M., Golestan, B., Ayromlou, H., . . . Darabi, M. (2012). Omega-3 fatty acids are protective against paclitaxel-induced peripheral neuropathy: A randomized double-blind placebo controlled trial. BMC Cancer, 12, 355.

Investigate omega 3 fatty acids in reducing the incidence and severity of paclitaxel-induced peripheral neuropathy

Patients were randomly assigned to receive omega 3 fatty acid supplements at a dose of 640 mg three times daily, or an identical gelatin placebo capsule. All patients received the intervention throughout treatment and for one month after chemotherapy treatment. Patients were evaluated prior to chemotherapy and one month after completion of chemotherapy. Evaluations were done by a single neurologist.

• N = 57           
• MEAN AGE = 45.9
• FEMALES = 100%
• KEY DISEASE CHARACTERISTICS: All had breast cancer and were receiving four courses of 175 mg/m² paclitaxel for positive node disease.

• SITE: Single site   
• SETTING TYPE: Outpatient  
• LOCATION: Iran

PHASE OF CARE: Active antitumor treatment

Double-blind, placebo-controlled, randomized trial

• Total peripheral neuropathy score including sensory symptoms, pin sensibility, tendon reflexes, and nerve conduction studies of sural and peroneal nerves from scores for individual items of 0-4
• Unilateral nerve conduction studies
• Serum concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)

70% of patients receiving omega 3 fatty acid supplements did not develop peripheral neuropathy, compared to 40% in the placebo group (odds ratio = 0.3, .95% CI = 0.10–0.88, p = .029). There was a non-significant trend toward lower severity of symptoms in those receiving omega 3 fatty acids. No significant differences existed between groups in individual nerve conduction study results. Significant differences did exist between groups in serum EPA and DHA concentrations (p < .005) with higher levels in the experimental group. No relationship existed between serum concentrations and peripheral neuropathy scores.

Findings suggest that oral supplementation with omega 3 fatty acids may have a protective effect for development of peripheral neuropathy in patients receiving paclitaxel.

• Small sample < 100
• Measurement/methods were not well described.
• Measurement validity/reliability was questionable.
• Findings were not generalizable.
• Study was underpowered by the authors’ report and calculations.
• The specific grading of findings to calculate the peripheral neuropathy score is not well defined and is not a commonly used and validated scoring approach.
• There was a limited timeframe of follow-up. 
• Findings may not be applicable in patients receiving different neurotoxic drugs.

Findings suggest a neuroprotective effect of omega 3 fatty acid supplementation. These are promising results, which warrant further research in well-powered studies and in the context of other types of neurotoxic chemotherapeutic agents.