Breast cancer survival rates improving

Breast cancer treatments designed to prevent a return of the disease after surgery have had a dramatic impact on the long-term survival of women, scientists report today.

For women with the most common form of the disease, death rates over 15 years have fallen by around half, thanks to combinations of chemotherapy and the hormone treatment tamoxifen.

The follow-up investigations, reported in the Lancet today, come from pooled data on 145,000 women involved in 194 trials. The survey, the largest such analysis of worldwide results, was conducted by the Early Breast Cancer Trials Collaborative Group.

It involved women whose breast cancer was detected only in the breast, or in some cases, also in lymph nodes, and whose tumours could be removed by surgery.

However, small numbers of cancerous cells can remain and unless stopped can grow back into life-threatening tumours, so adjuvant treatments have been introduced.

A patient of any age who had no cancer in the nodes might have a 25% chance of dying in 15 years through recurrence of cancer if she only received surgery, or surgery plus radiotherapy. But six months of treatment by anthracycline-based drugs reduced this to 16% for women under 50 and 21% for 50- to 69-year-olds.

The addition of five years' tamoxifen with the other drugs to combat hormone-sensitive early breast cancer, the most common form of the disease, improved the rates further. Among the under-50s, the original 25% risk of death fell to 12%, and for 50- to 69-year-olds to 15%.

None of the trials under scrutiny involved new drugs introduced since the mid-1990s.