C. Kent Osborne, MD, director of the Dan L. Duncan Comprehensive Cancer Center at Baylor College of Medicine, discusses his take home message for physicians treating patients with HER2-positive breast cancer. Osborne says the role of HER2-positivity is complicated.

Not only should physicians analyze whether the patient is negative or positive of HER2, but Osborne says they should also pay attention to what level of amplification is precent and what percentage of cells are HER2-positive. Evaluating how positive and what percentage of cells are effected is important in making these treatment decisions.

In patients where only 10% to 15% of the cells express HER2, HER2-targeted agents may not be the most appropriate choice. For example, T-DM1 will not be able to reach all cells if they are not all HER2-positive, and there are some data suggesting this is the case, Osborne notes.

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C. Kent Osborne, MD, discusses the important take home message for physicians treating patients with HER2-positive breast cancer. Osborne says the role of HER2-positivity is complicated.

Dr. Osborne on Evaluating HER2 Positivity in Breast Cancer

C. Kent Osborne, MD, director, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, discusses pertuzumab (Perjeta) in HER2-positive breast cancer.

The NEOSPHERE study showed that adding pertuzumab to trastuzumab (Herceptin) doubled the complete pathological response rate in the neoadjuvant stetting when it was combined with docetaxel.

Pertuzumab was also used in the APHINITY trial, results of which have not been published, but are indicating that pertuzumab provides some additional benefit in the adjuvant setting, says Osborne.

Kent Osborne, MD, director, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, discusses pertuzumab (Perjeta) in HER2-positive breast cancer.

Dr. Osborne on Pertuzumab in HER2+ Breast Cancer

C. Kent Osborne, MD, director, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, discusses targeting the HER2 pathway in breast cancer.

Osborne says that chemotherapy may be avoidable by blocking the HER2 pathway with targeted therapies. Along with his collegues, Osborne hypothesizes that it would be more effective to use more targeted agents to block the pathway, as trastuzumab (Herceptin) cannot block all of the receptors alone.

Studies were then done using dual HER2-targeted therapies without chemotherapy with pathologic complete remission rates ranging between 20% and 40%, suggesting that some patients with HER2 overexpressing tumors may not need to undergo chemotherapy at all.

Dr. Osborne Discusses Targeting the HER2 Pathway in Breast Cancer

C. Kent Osborne, MD, director, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, discusses the benefits of dual-targeted therapy for patients with HER2-positive breast cancer.

The trials of dual-targeted therapy have exhibited more benefits than trastuzumab (Herceptin) alone in patients with HER2-positive breast cancer, explains Osborne.

However, in the adjuvant setting this benefit was not as noticeable when paired with aggressive chemotherapy regimens. The chemotherapy destroys the same cells as the dual-targeted therapy, allowing there to be no noticeable benefit. The benefit of the dual-targeted therapy is that chemotherapy is avoided, states Osborne.

Dr. Osborne on the Benefits of Dual-Targeted Therapy for HER2+ Breast Cancer

C. Kent Osborne, MD, director, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, discusses the death of chemotherapy and rise of targeted agents in the treatment of patients with HER2-positive breast cancer.

The era of chemotherapy in HER2-positive breast cancer has ended, says Osborne, as genomic medicine that targets specific abnormalities within tumors is showing great effect.

According to Osborne, targeting the driver and alternate escape pathways of these tumors is next on the agenda for these agents.

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Dr. Osborne Discusses the Future of Treatment in HER2+ Breast Cancer

C. Kent Osborne, MD, professor of medicine and molecular and cell biology, Baylor College of Medicine, discusses the impact of the results of the PRIME 2 trial, which looked at radiotherapy after surgery in women over 65 years old with breast cancer.

Since this is not the only study that suggests that certain therapies can be avoided, Osborne feels that the results of this study will be practice changing. Even though the radiation therapy did reduce the risk of local recurrence, the differences were not great and the overall outcome was not different.

Osborne says that even in the rare case that a patient does recur in the breast without radiation, that patient can be salvaged very well by having another lumpectomy and radiation or by doing a mastectomy. However, this can be avoided in the majority of patients by not conducting radiation therapy.

C. Kent Osborne, MD

Articles

Dr. Osborne on Evaluating HER2 Positivity in Breast Cancer

Dr. Osborne on Pertuzumab in HER2+ Breast Cancer

Dr. Osborne Discusses Targeting the HER2 Pathway in Breast Cancer

Dr. Osborne on the Benefits of Dual-Targeted Therapy for HER2+ Breast Cancer

Dr. Osborne Discusses the Future of Treatment in HER2+ Breast Cancer

Dr. Kent Osborne Discusses the PRIME 2 Trial