Breast cancer has a variety of subtypes, each with its own characteristics and treatment options. HER2-positive breast cancer is a subtype that affects approximately 20% of all breast cancer patients. HER2-positive tumors produce too much of the HER2 protein, which can contribute to cancer growth and spread. Better understanding the biology of HER2-positive breast cancer can help make better treatment options available to patients.
HER2 Biology
HER2 is a protein found on the surface of cells. In normal cells, HER2 helps to regulate cell growth and division. However, in HER2-positive breast cancer, the cells produce too much of this protein, leading to uncontrolled cell growth and division. HER2-positive breast cancer tends to be more aggressive than other breast cancer subtypes, but it is also more likely to respond to treatments that target HER2.
Treatment Options
The treatment of HER2-positive breast cancer has come a long way in the past few decades. In the past, HER2-positive tumors tended to be more resistant to standard chemotherapy and hormone therapy. However, the development of targeted therapies that specifically target the HER2 protein has revolutionized the treatment of this subtype. These therapies include monoclonal antibodies that bind to the HER2 protein and inhibit its function, as well as small molecules that target the HER2 signaling pathway.
Current Clinical Trials
Although HER2-targeted therapies have improved outcomes for patients with HER2-positive breast cancer, there is still a need for better treatments. Many clinical trials are underway to investigate new therapies or combinations of existing therapies. For example, researchers are testing the use of immunotherapy in combination with HER2-targeted therapies, as well as investigating novel HER2-targeted agents that may be more effective than current options.
Prognosis
HER2-positive breast cancer tends to have a worse prognosis than other breast cancer subtypes, but the use of HER2-targeted therapies has improved outcomes for these patients. With appropriate treatment, many patients with HER2-positive breast cancer can achieve long-term remission or even complete cure. However, not all patients respond to these therapies, and some may experience side effects. Future Directions
Despite the progress made in the treatment of HER2-positive breast cancer, there is still much to be learned about this subtype. Researchers continue to investigate the underlying biology of HER2-positive tumors and to develop novel therapies. Additionally, there is a need for better biomarkers to predict response to therapy and to identify patients who may benefit from alternative treatment approaches.
HER2-positive breast cancer is a complex and challenging subtype of breast cancer. However, the development of targeted therapies has greatly improved outcomes for patients with this condition. With ongoing research efforts, we can hope that outcomes for patients with this subtype of breast cancer will continue to improve.
References
Mitri Z, Constantine T, O'Regan R. The HER2 Receptor in Breast Cancer: Pathophysiology, Clinical Use, and New Advances in Therapy. Chemother Res Pract. 2012;2012:743193. doi: 10.1155/2012/743193. Epub 2012 Dec 20. PMID: 23320171; PMCID: PMC3539433.