Tamoxifen is the most commonly prescribed adjuvant therapy for breast cancer and the only such treatment licensed in the UK for pre-menopausal women. Evidence shows one tablet a day for five years can significantly improve survival rates.
But researchers – who studied more than 2,000 women taking tamoxifen – found over half of subjects failed to finish the five-year course. A third stopped taking the drug within three and a half years, and one in 10 stopped within the first year.
Around 20% of the women also admitted they had regularly forgotten to take a tablet every day, the researchers said online in the British Journal of Cancer.
Study author Alastair Thompson, professor of surgical oncology at Ninewells Hospital, Dundee, said: ‘This study paints a worrying picture. Tamoxifen is prescribed for five years to offer the best chance of surviving breast cancer, and not taking the tablets means that many women could be disadvantaged.’
Victoria Harmer, a breast cancer clinical nurse specialist at St Mary’s Hospital in Paddington, London, cited a number of possible reasons why so many patients failed to finish a five-year course.
‘Tamoxifen is an extremely good and very sophisticated treatment for breast cancer but, because it is only a tablet, patients may place less importance on it than they would on chemotherapy,’ she said.
‘There are also the psychological implications of the side-effects – such as weight gain, hot flushes and night sweats – which can have a significant impact on a patient’s body image.
‘It is important nurses give advice on coping with these vasomotor side-effects and involve women in discussions about their treatment which could impact on their quality of life for a substantial length of time,’ Ms Harmer added.