Giving women with a certain type of breast cancer Herceptin for one
year following standard chemotherapy may improve their survival, according to
an article in this week's issue of The Lancet.
Around 15-25% of women with early breast cancer have a type called HER2-receptor
positive disease. Herceptin has been shown to reduce the risk of disease recurrence
in women with HER2-positive early breast cancer.
In the study, Ian Smith of the Royal Marsden Hospital in London and colleagues
assessed the effect of the drug on overall survival after a two year follow-up.
During the trial 1,703 women were randomised to receive Herceptin for one year
after surgery and chemotherapy and 1,698 women were assigned to the control
group (observation only). They found that more deaths occurred in the observation
group than in the drug group (90 vs 59), which corresponds to a survival benefit
of 2.7% after 3 years. There were more serious side effects in the Herceptin
group than in the observation group.
Herceptin has been linked to a number of complications suffered by breast cancer
patients, notably with regard to heart problems. The National Institute for
Health and Clinical Excellence (NICE) recommends all women should receive tests
on how well their heart is working before being prescribed the drug.
The Herceptin website states that ‘treatment can result in reduced heart
function and congestive heart failure. The risk of these heart problems was
higher in people who received both Herceptin and a certain type of chemotherapy
(anthracycline). Your doctor may need to stop or strongly consider stopping
Herceptin if you have a significant drop in your heart function.’
Despite the risks however, Dr Smith believes that the results of his study
indicate that Herceptin "shows a significant overall survival benefit in
early breast cancer over observation alone after chemotherapy,” he says.
“The survival benefit that has emerged over such a short period emphasises
the potential of this approach and underlines the importance of developing further
specific targeted therapies in breast and other cancers.”