Global Trends in HER2+ MBC

Volkmar Müller, MD, Prof Dr: Welcome to this OncLive® Peer Exchange, “The Changing Landscape of HER2+ Metastatic Breast Cancer.” I’m Volkmar Müller from the University Medical Center Hamburg-Eppendorf, in Germany. Joining me today through virtual discussion are my colleagues who have great expertise in the field.

Carmen Criscitiello, MD, PhD: I’m Carmen Criscitiello, medical oncologist at the European Institute of Oncology and assistant professor at the University of Milan, Italy.

Giuseppe Curigliano, MD, PhD: My name is Giuseppe Curigliano, I work at the European Institute of Oncology and University of Milan.

Tiffany A. Traina, MD: I’m Tiffany Traina. I’m a breast medical oncologist at Memorial Sloan Kettering Cancer Center in New York City.

Volkmar Müller, MD, Prof Dr: Thank you for being here. Today we will review treatment approaches for HER2-positive metastatic disease. We will be discussing new data from recent congresses and how these results might impact our clinical practice in the future. It’s a great opportunity to have a multinational board, as we can discuss broad perspectives. In the first segment we will cover the current treatment landscape for HER2+ metastatic disease from different perspectives. Are there differences between various regions of the world in the incidence and other factors of HER2+ metastatic disease?

Carmen Criscitiello, MD, PhD: Breast cancer is the most diagnosed cancer worldwide. We have more than 2 million new cases yearly, and it accounts for roughly 12% of new total cancer cases; it’s the leading cause of cancer among women. HER2+ breast cancer accounts for 15% to 20% of all breast cancers, and the incidence rates are highest in America, Australia, and Europe, and lowest in Asia. Twelve percent of all breast cancer cases are HR+ [hormone receptor-positive], HER2+, while 5% are HR-negative, HER2+, the lowest rates for all races and ethnicities. Up to 50% of patients with HER2+ breast cancer will develop brain metastases throughout the course of the disease, and approximately 50% of patients with HER2+ breast cancer and brain metastases die from intracranial disease progression. This is an important topic for HER2+ metastatic breast cancer, and the incidence of brain metastases appears to be higher in patients with HR-, HER2+ tumors compared to patients with HR+, HER2+ tumors.

Giuseppe Curigliano, MD, PhD: I completely agree of course on the epidemiology described. It’s quite clear that in the United States and the Western world we have a higher incidence with respect to Asia. In terms of biology, it’s more common to have HER2+ breast cancer in younger, premenopausal and postmenopausal women than in the elderly population because there are studies addressing patients over 75, usually there is a lower incidence of HER2 positivity.

Tiffany A. Traina, MD: One thing that we’ve observed over the past several years is, the introduction of highly active drugs has reduced the number of patients we’re seeing in the first-line metastatic setting, as the influence of those highly active therapies is curing women who are diagnosed with early stage HER2+ breast cancer.

Volkmar Müller, MD, Prof Dr: Yes, that may be true especially for countries that have available adjuvant setting treatment, which is also influencing metastatic disease.

Transcript edited for clarity.