High dose chemotherapy followed by bone marrow transplant is not an effective way to improve breast cancer survival rates, according to the preliminary results of four ongoing clinical trials.

For almost a decade, and without any proof of its effectiveness, ultra high doses of chemotherapy, followed by bone marrow transplant to remedy the destruction to the immune system, has been a standard treatment for American women with advanced or recurrent breast cancer. Indeed, many women feel that they are losing out if they don't have the therapy.

However, new information gleaned by the National Cancer Institute from four studies of 2,100 women in the US, Scandinavia and France has found no difference in survival between those who had the high dose regime and those who had lower doses of chemotherapy.

A fifth study, however, did find a benefit in patients with positive lymph nodes. After more than five years follow up, 17 per cent of those who had transplants had died, compared with 35 who did not.

The five studies are not due to conclude for another five years. However, Alan Lichter, president of the American Society of Clinical Oncology, comments that even if the studies do eventually find some benefit in the procedure, it will be small (BMJ, 1999; 318: 1093).