Olubukola Ayodele about HER2 low breast cancer

Olubukola Ayodele shared a post on LinkedIn:

”Let’s talk about HER2 low breast cancer.

The classification of breast cancer subtypes is based on the presence of specific receptors on the surface of cancer cells. These subtypes include HR+/HER2- (66%), HER2+ (19%), and TNBC (14%). Traditionally, breast cancers are classified as HER2+ if they exhibit a score of 3+ on immunohistochemistry (IHC) or if they are amplified by in situ hybridization (ISH). However, the heterogeneous nature of breast cancer cells reveals that even those classified as HER2 negative may still demonstrate some level of HER2 expression. This understanding has led to the emergence of a new classification known as HER2 low (2+ and 1+) and ultralow (0, with faint membrane staining of <10%). It is estimated that 60-65% of HR+/HER2- breast cancers are HER2 low and 20-25% are HER2 ultra low.

Historically, available anti-HER2 therapies have shown the greatest efficacy in cancers classified as 3+. However, the development of antibody-drug conjugates (ADCs), which are considered smart chemotherapy, has shifted the treatment approach for HER2 low metastatic breast cancer.

The results of the Destiny Breast 04 trial in 2022 revealed significant improvements in median progression-free survival (mPFS) and median overall survival (mOS) with the use of Trastuzumab Deruxtecan (T-Dxd) compared to standard single-agent chemotherapy in heavily pretreated HER2 low patients. Similarly, the results of the Destiny Breast 06 trial in 2024 demonstrated improved mPFS in both HER2 low and ultralow metastatic breast cancer (MBC) with T-Dxd. These findings have established T-Dxd as the standard of care for this patient population.

It is concerning that despite the potential benefits of this treatment, some patients are unable to access it due to regional variations in drug availability. These are the type of access to care disparities that we are hoping to spotlight and address at the upcoming Cancer Health Disparities Day Event at the House of Commons on 15th November 2024, as part of the London Global Cancer Week.

Efforts should be made to ensure that effective treatments, such as T-Dxd, are accessible to all patients in the UK, regardless of their geographic location.”

Source: Olubukola Ayodele/LinkedIn

Olubukola Ayodele is a Consultant Medical Oncologist at the University Hospitals of Leicester NHS Trust, specializing in breast and genitourinary malignancies, including germ cell tumors. She is also an honorary Senior Lecturer at the University of Leicester and heads the Breast Cancer Clinical Trials Unit at the Leicester Cancer Research Centre. Dr. Ayodele’s work includes numerous publications, clinical trials, and collaborative research projects on molecular drivers and biomarkers in breast cancer. She is a member of ASCO, ESMO, ACP and UKBCG.