Cancer doctors told to stick to proven treatment

A panel of oncologists yesterday urged doctors to stick to the time-tested drug tamoxifen in the treatment of breast cancer despite evidence that newer drugs may do a better job of preventing recurrence.

Studies on a new generation of drugs called aromatase inhibitors have initially shown them to be slightly more effective at preventing a relapse than tamoxifen. Their emergence last December was initially hailed as a breakthrough.

However, the American Society of Clinical Oncology, the world's largest organisation of cancer doctors, who convened an expert panel to review the issue, concluded yesterday it was too early to tell what the benefits and the risks could be, and urged doctors to be cautious about their wholesale use.

It would take at least a few years of study before there is certainty of their advantages as well as their possible risks, the panel told the society's meeting in Orlando Florida.

"Clearly if the difference was very, very dramatic, that would colour one's thinking, but the difference was small. It's proper caution to wait and see what happens before changing practice," said Dr Eric Winer, of Boston's Dana-Farber Cancer Institute, and chairman of the 18-member panel.

Tamoxifen has been the standard drug for 20 years for women who have had surgery for breast cancer. It works by blocking the effects of the female hormone oestrogen, which can fuel cancer growth. The aromatase inhibitors also affect the body's production of oestrogen, although in a different way.

"At this point, we would not recommend that doctors and patients start using this as the standard hormonal therapy in postmenopausal women"

Dr Eric Winer

At least 10 studies involving over 50,000 women are under way to compare various aromatase inhibitors with tamoxifen. "Give it two or three years, and we will be in a different place for comparing the drugs," Dr Winer said.