'HRT trebles risk of ovarian cancer'

Public confidence in hormone replacement therapy was dealt a new blow today after research showed it can more than treble the risk of ovarian cancer.

British women who take a certain type of HRT faced a safety scare last week after US scientists halted a major study into its effects because of the risks of breast cancer, heart attacks and strokes.

Now a new study, also in the US, has found that another type of HRT can put women at greater risk of developing ovarian cancer. Research involving more than 44,000 women found those who used oestrogen-only HRT were 60 per cent more likely to develop ovarian cancer than those who never had hormone replacement. Women who used oestrogen-only therapy for 20 years or more had a three-fold increased risk of the disease.

However, the likelihood of an individual getting ovarian cancer was very small. Among the 44,241 women taking part, 329 developed the disease, and only 16 cancers occurred in the group using HRT for more than 20 years.

Experts urged women not to panic. Dr Anne Szarewski, clinical director of Cancer Research UK, said: "The women in this study had been taking HRT for a very long time - some of them were in their eighties - while women in this country tend to only take HRT for the duration of symptoms such as hot flushes, and then stop after five or six years. Another factor is that women in this country who have hysterectomies are more likely to have their ovaries removed than in the US, so they are not so much at risk of ovarian cancer."

HRT normally consists of two female hormones, oestrogen and progesterone, as progesterone protects against cancer of the womb lining - a known hazard linked to oestrogenonly treatment. But many women who have had hysterectomies are given oestrogen-only HRT. The increased ovarian cancer risk found by the research was seen among women with and without wombs. Dr James Lacey and colleagues from the National Cancer Institute in Bethesda, Maryland, questioned the women about HRT and ovarian cancer between 1979 and 1998.

All were post-menopausal and had an average age of 56.6 at the start of the investigation. Last week's findings from an eight-year study of more than 16,000 women, called the Women's Health Initiative, caused a furore, with the US researchers abandoning it after five years when they found the risks of HRT outweighed the benefits.