Posted on Jun 10, 2023

A new study conducted in China and accepted as a poster at the ASCO congress in Chicago, has shown that MammaTyper®, an RT-qPCR assay, has the ability to accurately distinguish between HER2-low/neg breast cancer tumours. This means that therapies such as Trastuzumab deruxtecan that are specifically designed to target these types of tumours can be prescribed where appropriate and treatment is more likely to be successful.

Consisting of 793 cases, this study investigated the ability of MammaTyper® as an alternative to IHC to distinguish HER2 low/neg expression populations. In a number of cases, MammaTyper® showed that the long-term prognosis of ‘HER2-low’ defined patients was significantly better than ‘HER2-neg’ patients. However, when the samples were tested using classic ImmunoHistoChemistry (IHC) methods, this same distinction could not be made, suggesting that IHC could not accurately determine the amount of HER2 expression and patient prognosis in the same way.

New drugs, such as Trastuzumab deruxtecan can significantly improve overall survival for patients with HER2-low/neg tumours so it is essential that tumours are accurately subtyped, in the first place, so that clinical professionals can have confidence in the treatment paths that they recommend. The study concluded that ERBB2 mRNA expression as a companion diagnostic biomarker of HER2-ADC drugs in HER2-low populations warrants further exploration.

MammaTyper® is the first real innovation in subtyping breast cancer in decades. Using RT-qPCR technology proven during the COVID 19 pandemic, the multigene test works through an easily replicated and quantitative measurement of marker gene expression, classifying each sample as a St. Gallen subtype. Results are standardised and non-subjective.

Robustly reproducible, it avoids many of the common pre-analytical errors in the pathology lab. Using RT-qPCR to subtype breast cancer tissue is a valuable resource for pathologists and provides the reassurance that accurate subtyping will result in women getting the best treatment for their individual case.

“Advances in targeted treatments for breast cancer are happening at a fantastic rate,” said Rich Hughes at Cerca Biotech, the company behind MammaTyper®. “However, clinicians need to be confident that they are choosing the right targeted treatment in every individual case. For HER2-low/neg tumours, it is clear that IHC just isn’t accurate enough anymore and new diagnostic tools are needed. MammaTyper® can give pathologists the confidence to subtype breast cancer tissue accurately and quickly and provide a clear picture to clinicians and patients.”


For more details on this study, please see or contact

Recent research studies undertaken in the UK, Portugal and China concluded that MammaTyper® could provide a reliable, efficient, and reproducible alternative to the molecular subtyping of breast cancer tumours. For more details on these studies, please see

MammaTyper® is part of Cerca Biotech, a German-based diagnostic company focused on bringing innovative solutions to the oncology and women’s health market. Cerca Biotech strives to introduce the best tests to meet clinical needs at an affordable cost, with clinical accuracy and rapid results at the core. For more information, please visit