An interventional study of TSO500 Assay in Breast Cancer, sponsored by Cancer Trials Ireland. Recruiting at 3 sites in Ireland. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-02-20.
Sponsored by Cancer Trials Ireland · Not applicable, Interventional, and Diagnostic
This study aims to provide information about the genomics of your breast cancer which your oncologist can use to enhance the treatment of your disease possibly enabling more targeted and personalised therapy.This study will carry out TruSight Oncology Comprehensive (TSOComprehensive) testing on breast cancer tumour tissue that was collected at the time of your breast cancer diagnosis or during your breast surgery or if you have brain metastasis and you have had a biopsy for this. The TruSight Oncology Comprehensive assay is a next-generation sequencing (NGS) test used to analyse cancer-related genomic changes in patients, offering a comprehensive view of potential mutations and other alterations that can impact treatment decisions. The TruSight Oncology Comprehensive assay is CE-IVD marked for use in Europe, meaning that it complies with the relevant EU regulation, for comprehensive genomic profiling for different types of cancer. It analyses 523 cancer-relevant genes from both DNA and RNA to identify variations. It will also look for changes and mutations which may affect cell growth and stability. By identifying relevant mutations and biomarkers, the assay can help oncologists select the most appropriate treatment strategies with the aim of improving patient outcomes.
This is a pragmatic single-arm diagnostic interventional study. The study will use the Illumine TruSight Oncology 500 assay for research use only under Article 5(5) in-house exemption of the EU IVDR (EU 2017/746). Testing will be performed on paraffin embedded tumour tissue. This assay will target 523 genes to assess all somatic DNA variants as well as microsatellite instability (MSI), tumour mutational burden (TMB), and homologous recombination deficiency (HRD). Testing will be performed centrally in the molecular diagnostics laboratory (ISO 15189 accredited) at Beaumont hospital on the Next Seq 550Dx. This lab currently uses this platform for diagnostic comprehensive genomic profiling. Bioinformatic analysis will be undertaken to identify clinically actionable mutations. Results will be discussed at the multi-disciplinary Molecular Tumour Board, Beaumont RCSI Cancer Centre and full data along with treatment recommendation will be provided to the treating oncology team.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 1,600 is above the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Cancer Trials Ireland is the lead sponsor of 71 studies on the registry; 8 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
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.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
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.
Utilisation of TSO500 assay to identify somatic, clinically actionable somatic in the primary breast tumour and, where relevant, brain metastatic tumour to the treating physician to inform clinical management of participating patients
Diagnostic Test: TSO500 Assay
Utilisation of TSO500 assay to identify somatic, clinically actionable somatic in the primary breast tumour and, where relevant, brain metastatic tumour to the treating physician to inform clinical management of participating patients.
Proportion of enrolled patients with at least one clinically actionable mutation identified by PRISM diagnostics compared with standard-of-care diagnostics.
Time frame: At the time of therapeutic decision following diagnostic assessment (up to 6 weeks from enrollment).
Plan to share: Undecided
Started Nov 2025 (actual). Primary completion is estimated for Dec 2030, 61 months after the start.
Of 2,661 non-industry interventional studies with no phase under Breast Neoplasms, half reached primary completion within 33 months of starting (the median), counting those still running; a quarter within 16 and three quarters within 66. This study's planned 61 months is above that.
Counting every sponsor, half of 2,771 studies reached it within 33 months; a quarter within 15 and three quarters within 66.
How these figures are worked out, and which studies are left out of them.
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Cancer Trials Ireland