An observational study in Metastatic Breast Cancer, sponsored by Hellenic Cooperative Oncology Group. Recruiting at 5 sites in Greece. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-14.
Sponsored by Hellenic Cooperative Oncology Group · Observational
Ample evidence has highlighted the significant clinical benefit of novel therapies for many patients with advanced breast cancer (aBC). The use of CDK inhibitors, antibody-drug conjugates (ADCs), immune checkpoint inhibitors (ICIs), and PARP inhibitors as first-line or subsequent treatments has improved progression-free survival (PFS) rates compared to conventional therapies. In selected cases, these treatments have also increased overall survival (OS), reshaping the therapeutic landscape for advanced breast cancer.
However, several key questions remain unanswered. For example, what should be the first-line treatment when multiple effective options are available? Determining the optimal sequence of drugs in successive lines of therapy is another major challenge. Furthermore, the development of resistance to treatment and the occurrence of severe adverse events that may lead to early discontinuation or fatal outcomes are pressing concerns.
That said, identifying robust predictive biomarkers of response or resistance is crucial for ensuring that patients receive the most effective treatment while avoiding unnecessary exposure to therapies that could cause harm without benefit. Additionally, when multiple effective options exist, selecting the optimal treatment algorithm for each patient based on clinical, pathological, and molecular biomarkers is essential.
We herein, aim at employing high throughput methodologies, such as Whole Exome Sequencing, circulating tumour DNA (ctDNA) analysis, digital pathology and radiomics analyses, as well as real-world data obtained both from patients records for the training of a ML-based algorithm that can predict response or resistance to a specific treatment, based on the genetic make-up of the patient and the molecular profile of the tumour.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 150 is below the median of 184 across 3,235 observational studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Hellenic Cooperative Oncology Group is the lead sponsor of 62 studies on the registry; 6 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The study will include patients with histologically confirmed, advanced breast cancer of one of the following subtypes: i) Hormone receptor positive and/or ii) HER2-positive or -low or iii) triple negative breast cancer (TNBC)
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HER2
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients receiving treatment with an Antibody-Drug conjugate (e.g Trastuzumab-Deruxtecan, Sacituzumab-Govitecan)
Patients receiving treatment with an immune checkpoint inhibitor (ICI) (e.g pembrolizumab)
Patients receiving treatment with a PARP inhibitor (e.g Olaparib)
This study also gives Pembrolizumab, Olaparib, Trastuzumab deruxtecan, Sacituzumab govitecan. No intervention listed here names it: that was found by reading the record.
Progression-free survival (PFS)
Correlation of genetic and molecular/circulating biomarkers with PFS, with PFS defined as the time from enrollment to disease progression or death
Time frame: Through study completion, 5 years
Overall Survival (OS)
Correlation of genetic and molecular/circulating biomarkers with OS, with OS defined as the time from date of metastatic diagnosis to last follow-up (36 months, post enrollment) or death
Time frame: Through study completion, 5 years
Objective Response Rate (ORR)
Correlation of genetic and molecular biomarkers with response to treatment
Time frame: Through study completion, 5 years
Evaluation of AI-predictive algorithm
Evaluation of the efficiency of the AI-predictive algorithm, by determining key metrics such as sensitivity and specificity
Time frame: Through study completion, 5 years
Plan to share: No
Started Oct 2024 (actual). Primary completion is estimated for Oct 2029, 60 months after the start.
Of 1,191 non-industry observational studies under Breast Neoplasms, half reached primary completion within 58 months of starting (the median), counting those still running; a quarter within 25 and three quarters within 139. This study's planned 60 months is close to that.
Counting every sponsor, half of 1,380 studies reached it within 55 months; a quarter within 25 and three quarters within 126.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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Hellenic Cooperative Oncology Group