Blood drop transforming into a flower, symbolizing liquid biopsies and cancer care.

Beyond the Scan: How 'Liquid Biopsies' Could Revolutionize Breast Cancer Staging

Reese Marlowe in Health & Wellness August 2025 • 4 min read.

"New research spotlights the power of circulating tumor cell counts to predict outcomes in metastatic breast cancer, offering a less invasive approach to staging and treatment decisions."

Metastatic breast cancer (MBC) is a complex disease, and experts are always looking for better ways to understand how it will progress in individual patients. Traditional methods rely on physical exams, imaging, and biopsies. Now, a less invasive technique called a "liquid biopsy" is showing great promise.

Liquid biopsies analyze circulating tumor cells (CTCs) in a blood sample. The number of CTCs can provide valuable information about the aggressiveness of the cancer and how well a patient is likely to respond to treatment. This approach offers a potential way to refine how MBC is staged and treated.

A recent international study analyzed data from thousands of MBC patients. The findings suggest that CTC counts can effectively divide patients into subgroups with different survival rates, regardless of the cancer's subtype or prior treatments. This article delves into this research and what it could mean for the future of breast cancer care.

Unlocking the Secrets in a Blood Sample: CTCs and MBC

Blood drop transforming into a flower, symbolizing liquid biopsies and cancer care.

The study, which pooled data from 18 international centers, involved 2,436 MBC patients. Researchers used a threshold of 5 CTCs per 7.5 ml of blood to classify patients into two groups: those with a more indolent (slow-growing) form of the disease and those with a more aggressive form. They then looked at how survival differed between these groups.

The results were striking. Patients with fewer than 5 CTCs (the indolent group) lived significantly longer than those with 5 or more CTCs (the aggressive group). This difference held true regardless of the type of breast cancer (hormone receptor-positive, HER2-positive, or triple-negative) and whether the patient had received prior treatment.

Overall Survival: Patients with indolent disease had a median overall survival of 36.3 months, compared to just 16 months for those with aggressive disease.
De Novo MBC: Even in patients newly diagnosed with stage IV breast cancer, CTC counts were predictive. The indolent group survived 41.4 months versus 18.7 months for the aggressive group.
Location Matters Less: The link between CTC count and survival held true whether the cancer had spread to the bones, liver, or other organs.

These findings suggest that CTC enumeration offers a valuable and easily accessible tool for understanding MBC. It can help doctors better assess a patient's prognosis and make more informed decisions about treatment strategies.

The Future of Breast Cancer Care: Personalized and Precise

This research adds to a growing body of evidence supporting the use of liquid biopsies in cancer care. By providing a real-time snapshot of the disease, CTC counts can help doctors move away from a one-size-fits-all approach and towards personalized treatment plans.

The study authors believe that CTC enumeration should be integrated into the standard staging process for MBC. They also suggest that future clinical trials should use CTC counts to stratify patients, ensuring that the right treatments are given to the right people.

While more research is needed, liquid biopsies offer a promising way to improve outcomes for women with metastatic breast cancer. They represent a significant step towards a future where cancer care is more precise, less invasive, and more effective.

About this Article -

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This article is based on research published under:

DOI-LINK: 10.1016/j.critrevonc.2018.12.004, Alternate LINK

Title: The Clinical Use Of Circulating Tumor Cells (Ctcs) Enumeration For Staging Of Metastatic Breast Cancer (Mbc): International Expert Consensus Paper

Subject: Oncology

Journal: Critical Reviews in Oncology/Hematology

Publisher: Elsevier BV

Authors: Massimo Cristofanilli, Jean-Yves Pierga, James Reuben, Alfred Rademaker, Andrew A. Davis, Dieter J. Peeters, Tanja Fehm, Franco Nolé, Rafael Gisbert-Criado, Dimitrios Mavroudis, Salvatore Grisanti, Mario Giuliano, Jose A. Garcia-Saenz, Justin Stebbing, Carlos Caldas, Paola Gazzaniga, Luis Manso, Rita Zamarchi, Angela Fernandez De Lascoiti, Leticia De Mattos-Arruda, Michail Ignatiadis, Luc Cabel, Steven J. Van Laere, Franziska Meier-Stiegen, Maria-Teresa Sandri, Jose Vidal-Martinez, Eleni Politaki, Francesca Consoli, Daniele Generali, Maria Rosa Cappelletti, Eduardo Diaz-Rubio, Jonathan Krell, Sarah-Jane Dawson, Cristina Raimondi, Annemie Rutten, Wolfgang Janni, Elisabetta Munzone, Vicente Carañana, Sofia Agelaki, Camillo Almici, Luc Dirix, Erich-Franz Solomayer, Laura Zorzino, Lauren Darrigues, Jorge S. Reis-Filho, Lorenzo Gerratana, Stefan Michiels, François-Clément Bidard, Klaus Pantel

Published: 2019-02-01

Everything You Need To Know

What exactly is a liquid biopsy, and how does it work in the context of breast cancer?

A "liquid biopsy" analyzes circulating tumor cells (CTCs) in a blood sample to provide insights into the aggressiveness of metastatic breast cancer (MBC). This method is less invasive than traditional biopsies and offers a real-time snapshot of the disease. The number of CTCs is a key indicator: higher counts often correlate with a more aggressive form of the cancer, while lower counts suggest a less aggressive, or "indolent", form of the disease.

Why are circulating tumor cell (CTC) counts important in understanding how metastatic breast cancer (MBC) will progress?

CTC counts are important in understanding how MBC will progress because they provide a predictive tool for patient survival. Research, including an international study with a large patient cohort, found that patients with fewer than 5 CTCs per 7.5 ml of blood had significantly longer survival times than those with 5 or more CTCs. This held true regardless of breast cancer subtype or prior treatments. This capability allows doctors to better understand the course of the cancer for each patient.

What are the implications of circulating tumor cell (CTC) counts for treating metastatic breast cancer?

The implications of CTC counts extend to personalized treatment plans for MBC. By providing information on disease aggressiveness, CTC counts help doctors move away from a generalized approach to treatment. If a patient has a high CTC count, indicating a more aggressive cancer, the doctor might opt for more intensive treatments. Conversely, a low CTC count could suggest a less aggressive approach is appropriate. This personalized care is crucial for improving patient outcomes and quality of life.

How did the study classify patients based on circulating tumor cell (CTC) counts, and what were the outcomes?

The study classified patients based on their CTC counts: those with fewer than 5 CTCs per 7.5 ml of blood were considered to have an indolent form of the disease, while those with 5 or more CTCs were considered to have a more aggressive form. The results showed a dramatic difference in survival rates between the two groups. This classification has implications for prognosis and treatment strategies, as it allows doctors to tailor their approach based on the patient's individual risk.

How do circulating tumor cell (CTC) counts predict survival rates in patients with metastatic breast cancer (MBC)?

The significance of CTCs lies in their ability to predict survival rates in MBC patients. Patients with an indolent form of the disease, characterized by low CTC counts, experienced a median overall survival of 36.3 months. In contrast, patients with a more aggressive form of the disease, marked by high CTC counts, had a median overall survival of only 16 months. This predictive power allows doctors to make more informed decisions about treatment, potentially improving patient outcomes. This was consistent regardless of where the cancer had spread, even to bones, liver, or other organs.