Preclinical evidence suggests Herceptin can restore and amplify responsiveness to hormonal therapy. The combination of Tykerb and Femara is FDA approved and is thought to work through this mechanism. A randomized phase III TAnDEM studyinvestigated Trastuzumab plus anastrozole versus anastrozole alone for the treatment of postmenopausal women with human epidermal growth factor in receptor 2-positive, hormone receptor-positive metastatic breast cancer. Patients who received trastuzumab and anastrozole had better PFS than patients that received anastrozole only. There was no difference in overall survival between the two treatments. The numbers of adverse events and severe adverse events were higher with the combination arm compared to anastrozole only arm. This was a crossover design, which may have interfered with finding a difference in survival between the two arms.
Much more research needs to be done and guidelines have not yet incorporated Herceptin and Arimidex as standard recommendation. The accompanying editorial suggested that the such evidence, “should be viewed as pioneering and hypothesis driven; they are likely to become obligatory references in the field of HER2 breast cancer.”
Bella Kaufman, John R. Mackey, Michael R. Clemens, Poonamalle P. Bapsy, Ashok Vaid, Andrew Wardley, Sergei Tjulandin, Michaela Jahn, Michaela Lehle, Andrea Feyereislova, Cédric Révil and Alison JonesTrastuzumab Plus Anastrozole Versus Anastrozole Alone for the Treatment of Postmenopausal Women With Human Epidermal Growth Factor Receptor 2–Positive, Hormone Receptor–Positive Metastatic Breast Cancer: Results From the Randomized Phase III TAnDEM Study JCO November 20, 2009 vol. 27 no. 33 5529-5537
Javier Cortes et al, How to Treat Hormone Receptor–Positive, Human Epidermal Growth Factor Receptor 2–Amplified Breast Cancer
JCO November 20, 2009 vol. 27 no. 33 5492-5494
Howard M. Stern Improving Treatment of HER2-Positive Cancers: Opportunities and Challenges Sci Transl Med Mar 28, 2012:127rv2
Locally recurrent or metastatic breast cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up
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