A daily dose of 1.8 grams of DHA also produced no adverse effects, according to a new study published in the British Journal of Cancer.
“Our data show for the first time that a dietary intervention targeted on DHA is a feasible approach that has potential to substantially increase survival in metastatic breast cancer patients treated with chemotherapy,” wrote the researchers, led by Dr Philippe Bougnoux from the French Institut National de la Santé Et de la Recherche Médicale (INSERM) U921 in Tours.
Being a phase II clinical trial, the research represents an “incentive to set up a prospective-controlled randomised trial aimed at identifying the place of dietary DHA in breast cancer treatments”, added the researchers.
Every year about 1.3 million women are diagnosed with breast cancer around the world, with just fewer than half a million deaths associated with the disease, according to the American Cancer Society (ACS).
While the incidence of the disease has increased by about 30 per cent over the last 25 years in the west, death rates have declined dur to improved detection and tratments, said the ACS.
The new study, if supported by additional research, suggests that DHA may help improve survival by sensitising tumours to chemotherapy, said Dr Bougnoux and his co-workers.
The Tours-based researchers recruited 25 women with breast cancer to participate in their open-label single-arm phase II study. As part of their anthracycline-based chemotherapy (FEC) regimen women were given additional DHA (1.8 grams per day, DHA-enriched triglyceride oil of algal origin, supplied by Martek Biosciences) for between 2 and 6 months.
After an average of 31 months, Dr Bougnoux and his co-workers found that the overall survival of women was 22 months, and reached 34 months in women with the highest DHA levels in their blood.
“Although the median time to progression (6 months) and overall survival (22 months) in our study were within the frame of published data, it should be stressed that our patient population had a particularly poor prognosis, as 68 per cent had liver metastases in addition to other sites of metastases,” stated the researchers. “The median overall survival of patients having liver metastases was reported to be 14 months.”
Importantly the DHA supplements during chemotherapy were not associated with any adverse side effects, they added.
Source: British Journal of Cancer
Volume 101, Pages 1978–1985, doi:10.1038/sj.bjc.6605441
“Improving outcome of chemotherapy of metastatic breast cancer by docosahexaenoic acid: a phase II trial”
Authors: P. Bougnoux, N. Hajjaji, M.N. Ferrasson, B. Giraudeau, C. Couet, O. Le Floch