Positive Health Online

Abstract

MAILLARD and colleagues, Laboratoire de Biologie des Tumeurs, Clinique d'Oncologie-Radiotherapie, Service de Gynecologie-Obstetrique, E.A. 2103, Unite de Recherche Associee Universite-INRA, CHU, Tours, France, investigated the question of whether n-3 fatty acids protect against the development of breast cancer .

Background

Experimental evidence exists to suggest that n-3 fatty acids such as alpha-linolenic acid (ALA ; 18:3, n-3) and long-chain n-3 polyunsaturated fatty acids (PUFAs) can inhibit the growth of breast cancer tumours and their spread to other body areas. Epidemiological studies have investigated the possibility that dietary n-3 PUFAs may protect against the development of breast cancer, but the results of these early studies were inconclusive. The authors of the present report conducted a clinical study to evaluate this question.

Methodology

Subjects were 241 patients with invasive non-metastatic breast cancer, and 88 patients with benign breast lumps who acted as controls. The investigators analysed the levels of fatty acids in adipose tissue, taken to be an indicator of the patients' past dietary consumption levels of fatty acids . Samples of adipose tissue were taken at the time of breast surgery. Individual fatty acid levels, expressed as a percentage of total fatty acids, were measured. Odds ratio estimates of breast cancer risk were calculated using unconditional logistic regression modelling. Data were adjusted for possible confounding factors such as age, height, menopausal status and body mass index.

Results

Breast cancer risk was found to be inversely linked with levels of n-3 fatty acid levels in breast adipose tissue . Women with levels of ALA in the upper third of the range of levels in the whole group had an odds ratio (OR) of 0.39 for breast cancer risk in comparison with those in the lower third. Those with levels of docosahexaenoic acid (DHA ; 22:6, n-3) in the highest tertile had an OR of 0.31 compared with those in the lowest tertile. Women with a ratio of long-chain n-3 to total n-6 fatty acids in the highest tertile had an OR of 0.33 compared with those in the lowest tertile.

Conclusion

The results suggest that n-3 fatty acids are protective against breast cancer and lend credence to the view that the ratio of n-3 to n-6 fatty acids is important in the development of breast cancer.

References

Maillard V et al. N-3 and N-6 fatty acids in breast adipose tissue and relative risk of breast cancer in a case-control study in Tours, France. International Journal of Cancer 98 (1): 78-83. Mar 2002.

Comment

A potentially highly significant result!