WOMEN diagnosed with breast cancer and treated with tamoxifen are traditionally advised to take the drug for five years. However results of two new trials indicate that 10 years is more effective, resulting in 25% less recurrent disease and 23% less deaths compared to those who take the drug for only five years.
Prof Fran Boyle AM, Director of the Patricia Ritchie Centre for Cancer Care and Research at the University of Sydney, advises that a consultation with a medical oncologist may be useful for women who have taken the drug for five years to discuss the benefits of extending to 10. You can read her Comment on the ground-breaking ASCO 2013 aTTom results here:
“Extending the duration of endocrine therapy for women with ER positive breast cancer has been investigated over the last 2 decades, as the propensity of this disease to have a bi-phasic relapse pattern has been recognised. Women were once told “if you get to 5 years you are out of the woods” and this advice is no longer given glibly. For women who remain premenopausal after 5 years of Tamoxifen, extending to 10 years is now a viable option to reduce late recurrence, based on combined results of aTTom (ASCO 2013) and ATLAS (Lancet 2012) trials. For women who become menopausal in the first 5 years of tamoxifen or were postmenopausal at diagnosis, earlier studies have shown that a switch to letrozole is a viable alternative (MA17 Goss 2005) with a lesser risk of endometrial cancer. Individual decision making should include an assessment of the risk profile of the cancer (high grade, node positive, Her 2 positive), the woman’s comorbidities (eg bone and joint health, cardiovascular risk factors, whether she has had a hysterectomy) and preferences for childbearing should be taken into account. Consultation with a medical oncologist at 5 years may be useful in weighing up the options.”
Prof Fran Boyle AM, University of Sydney and Mater Hospital, North Sydney.