A groundbreaking study published in Science Translational Medicine has demonstrated that liquid biopsy technology could revolutionise personalised cancer treatment for high-risk breast cancer patients. The research advances precision oncology by offering a less invasive, more accessible approach to predicting immunotherapy response.
What Is Liquid Biopsy and How Does It Work?
Liquid biopsy breast cancer testing involves analysing blood samples rather than surgically removing tissue from the tumour site. In this study, researchers performed RNA sequencing on 546 peripheral blood samples from 160 patients with high-risk, stage 2 or 3 HER2-negative breast cancers. The blood samples were collected repeatedly throughout treatment with either chemotherapy alone or in combination with immunotherapy.
The researchers focused on assessing the transcriptome—the transcription of genes involved in the clonal expansion and activation of antitumor immune cells called T cells. This approach allowed them to predict patient response to pembrolizumab, an immunotherapy drug commonly used in breast cancer treatment.
Why Liquid Biopsy Matters for Breast Cancer Patients
Traditional tissue biopsies are invasive procedures that provide a single snapshot of what is happening in the tumour at one specific moment. Liquid biopsy breast cancer testing offers several significant advantages:
The procedure is minimally invasive, requiring only a blood draw rather than surgical intervention. It can be repeated throughout treatment to monitor the evolving immune response in real time. The cost-effectiveness of blood sampling makes it more accessible than repeated tissue biopsies. Perhaps most importantly, it provides dynamic information about how treatment is working, allowing doctors to adjust therapeutic strategies as needed.
The study involved investigators from the I-SPY2 clinical trial, which operates across 42 trial locations and focuses on assessing novel treatment strategies for breast cancer subsets based on their molecular characteristics.
Implications for Precision Oncology in Australia and Globally
While this research was conducted in the United States, the implications extend to cancer patients worldwide, including those receiving treatment in Australia. Major Australian oncology centres participate in international research collaborations and clinical trials. Advances in precision oncology developed through studies like this one benefit patients globally as treatment protocols evolve based on the best available evidence.
The researchers concluded that while validation is needed, this new liquid biopsy approach has the potential to “guide immunotherapy decision-making, tailor treatment regimens, and advance precision oncology, not only in breast cancer but potentially in other solid tumours as well.”
The Future of Personalised Cancer Treatment
Immunotherapy has become a standard component of care for high-risk, early-stage breast cancers, yet it has shown limited success in shrinking tumours for some patients. New biomarkers that can improve treatment outcomes are urgently needed. Liquid biopsy breast cancer testing represents a significant step toward addressing this need.
Cell-free DNA testing, another form of liquid biopsy, is already used routinely in clinical practice for detection, diagnosis and therapeutic monitoring of various malignancies. The transcriptome-based approach demonstrated in this study adds another dimension to liquid biopsy capabilities, offering the potential to monitor immune response dynamically throughout treatment.
What This Means for You
If you or someone you care about is navigating breast cancer treatment, it’s important to understand that liquid biopsy technology is still being validated and is not yet standard practice in Australia. However, this research represents the direction that cancer care is heading—toward more personalised, less invasive approaches that allow treatment to be tailored to each individual patient’s unique biology and immune response.
As precision oncology continues to advance, staying informed about emerging diagnostic and treatment options can help you have more productive conversations with your oncology team about what might be available to you, either now or in the near future.
Educational disclaimer: This information is for educational purposes only and does not constitute medical advice. Always consult your oncologist or healthcare team regarding treatment options, diagnostic technologies, and clinical trials that may be appropriate for your individual situation.
Sources: Vanderbilt University Medical Center via News Medical; Sun, X., et al. (2026). Peripheral blood transcriptional profiling predicts tumour subtype and neoadjuvant chemoimmunotherapy outcomes in human breast cancer. Science Translational Medicine. DOI: 10.1126/scitranslmed.aec2358. Available at: Science Translational Medicine
