Back to Cancer Australia's website

Cancer Australia

Select a guideline

Recommendations for Aromatase inhibitors as adjuvant endocrine therapy

Clinical practice recommendations

Recommendations to an individual should be based on their risks without treatment, the benefits and harms of treatment, and their preferences. Recommendations should also take account of any uncertainties about long-term effects. In women at high risk of breast cancer recurrence, the known benefits of aromatase inhibitors are likely to outweigh their harms (both known and unknown). Conversely, in women at low risk of breast cancer recurrence, known or unknown harms of aromatase inhibitors could outweigh the known benefits. In women at intermediate risk of recurrence, the balance between benefits and harms is unclear.

Women at high risk of recurrence include those with involved lymph nodes, large primary tumours (>2cm) and high-grade tumours (grade 2–3). Women at low risk of recurrence include those with small, well-differentiated tumours and uninvolved lymph nodes. More extensive discussion of these issues can be found in the NBCC* Clinical Practice Guidelines for the Management of Early Breast Cancer .1

RECOMMENDATIONS LEVEL OF EVIDENCE AROMATASE INHIBITOR USED 
in trials on which recommendation is based
Adjuvant endocrine therapy is recommended for most women with hormone receptor-positive early breast cancer
Women should be informed of the potential side effects of the adjuvant endocrine therapy recommended to them, regardless of their risk of recurrence, and should be informed of any uncertainties about long-term effects    
Women receiving adjuvant endocrine therapy should be reviewed regularly and monitored for side effects by clinicians familiar with these drugs    
Reduction of bone mineral density in women receiving an aromatase inhibitor should be managed according to existing guidelines for women in general.8 This includes the
identification and treatment of women at high risk of osteoporosis
 I  
For post-menopausal women with hormone receptor-positive early breast cancer who are at HIGH risk of breast cancer recurrence:
If the woman has not started adjuvant endocrine therapy, it is recommended that adjuvant endocrine therapy starts with an aromatase inhibitor (rather than tamoxifen) II Anastrozole, Letrozole
If the woman has been on adjuvant endocrine therapy with tamoxifen for 2–3 years it is recommended that therapy be switched to an aromatase inhibitor II Anastrozole, Exemestane
If the woman has been on adjuvant endocrine therapy with tamoxifen for 5 years it is recommended that adjuvant endocrine therapy be extended with Letrozole II Letrozole
For post-menopausal women with hormone receptor-positive early breast cancer who are at INTERMEDIATE risk of breast cancer recurrence:
Decisions about whether to use an aromatase inhibitor or tamoxifen should be based on an assessment of the risks and benefits of treatment for that individual II  
For post-menopausal women with hormone receptor-positive early breast cancer who are at LOW risk of breast cancer recurrence:
Adjuvant endocrine therapy with tamoxifen is recommended (rather than with an aromatase inhibitor) for most low-risk women as described in the NBCC* Clinical Practice Guidelines for the Management of Early Breast Cancer (2001)1 because the balance between long-term benefits and harms of aromatase inhibitors is presently unclear for such women II  
For post-menopausal women with hormone receptor-positive early breast cancer who are intolerant of tamoxifen or who have a contra-indication to tamoxifen (regardless of risk of breast cancer recurrence):
Adjuvant endocrine therapy with an aromatase inhibitor is recommended II  

* In February 2008, National Breast Cancer Centre (NBCC), incorporating the Ovarian Cancer Program, changed its name to National Breast and Ovarian Cancer Centre (NBOCC). In July 2011, NBOCC amalgamated with Cancer Australia to form a single national agency, Cancer Australia, to provide leadership in cancer control and improve outcomes for Australians affected by cancer.

Published using CeCC Docbook Manager