Understanding Metastatic Breast Cancer: Exploring the Science

Abderrahmane Laadem, M.D., Head of Late-Stage Oncology Clinical Development

A More Complex Disease 

“While scientists have made significant progress in understanding cancer, the exact reasons why certain cancers, including breast, progress to metastatic or behave differently than others are not fully understood. Research has shown that differences at cellular and molecular levels play a crucial role in cancer progression. Early breast cancer is often driven by a defined set of molecular alterations, while metastatic breast cancer evolves into a genetically complex and heterogeneous disease.  

Metastatic cancer is tricky because it can keep changing in ways that make it harder to treat. It can develop new genetic changes, switch how its genes are turned on or off, and create different groups of cancer cells within the same tumor. All these changes help the cancer grow, spread to other parts of the body, and resist treatments.” 

How do these Differences Alter the Treatment Landscape?

Early-stage breast cancer is considered more treatable as the tumor burden is generally small. In these cases, the primary goal is to remove cancer cells through surgery then destroy any remaining cancer cells with radiation, and in some cases systemic therapies, to prevent recurrence.  

Metastatic breast cancer signifies the spread of cancer cells from the initial site in the breast to multiple locations throughout the body, rendering localized treatments such as surgery insufficient. Consequently, patients at the metastatic stage require systemic therapy which aims to manage symptoms, delay progression, and ultimately prolong survival. Systemic therapies range from hormone therapy and chemotherapy to immunotherapy and targeted therapies such as antibody drug conjugates.  

For patients with metastatic breast cancer, the treatment journey is more nuanced. Metastatic cancer tends to present as larger or multiple tumors, is more aggressive as it progresses and can even develop resistance to certain treatments, all creating a unique pathway for possible treatment strategies for each patient to discuss with their healthcare provider. Together, they must determine not only which treatment options to utilize, but what the right regimen sequence is as well.  

Peter Soonmo Kang, M.D., VP, Head of Late-Stage Clinical Development (3-ADC)

Emerging Breakthrough Treatments 

“The unwavering dedication of researchers at Daiichi Sankyo, led by the late, esteemed Dr. Toshinori Agatsuma, resulted in the creation and advancement of the Daiichi Sankyo proprietary DXd ADC Technology*. This breakthrough has been instrumental in developing innovative treatment options for patients with certain cancers, such as our HER2 directed ADC. 

What sets this treatment apart is its ability to bind to the HER2 receptor. This enables the delivery of our potent and unique payload, which enables a bystander antitumor effect**, resulting in elimination of both target and neighboring cells present in the tumor microenvironment.”