Validation of Molecular Diagnostic Assays to Detect Cancer Biomarkers in Blood & Primary Tumor in ER+/HER2- MBC

A Clinical Performance Study to Validate the Use of Novel Molecular Diagnostic Assays for the Detection of Cancer Biomarkers in Peripheral Blood and Primary Tumor Tissue Samples of Patients With Metastatic ER+/HER2- Breast Cancer

Conventional biopsy and surgical tumor resection are invasive procedures that capture only one instance of the progression of the tumor. However, the genome of tumor is not static, but it is constantly altered during treatment.

Liquid biopsy is a non-invasive approach based on the extraction of information through peripheral blood analysis. It makes it possible to characterize the development of a solid tumor in real time, through detailed molecular analysis of circulating genetic material in peripheral blood.

Study Overview

• Status: Completed
• Conditions: Breast Cancer
• Intervention / Treatment: Diagnostic test: PIK3CA kit

Detailed Description

Conventional biopsy and surgical tumor resection are invasive procedures that capture only one instance of the progression of the tumor. However, the genome of tumor is not static, but it is constantly altered during treatment.

Liquid biopsy is a non-invasive approach based on the extraction of information through peripheral blood analysis. It makes it possible to characterize the development of a solid tumor in real time, through detailed molecular analysis of circulating genetic material in peripheral blood.

Study procedure:

1. Initial Visit (V0-Baseline): For the purposes of the study the following information will be collected: the demographics, medical and social history, the characteristics of the disease (stage, molecular characterization e.t.c) and the treatment regimen that is followed. As part of the visit, 20 mL of peripheral blood will be drawn prior to their treatment according to physician's suggestion as per common clinical practice. Blood samples will be then sent to ACTC laboratory for plasma/CTC isolation, DNA and RNA extraction and subsequent test for biomarkers. Primary tumor tissue samples will be also collected
2. Follow-up visit (V1): Response to treatment by RECIST based on restaging CTs/MRIs will be documented during this visit, which will take place 3 months after treatment initiation. As part of the visit, 20 mL of peripheral blood will be drawn.

Blood samples will be then sent to laboratory for plasma/CTC isolation, DNA and RNA extraction and subsequent test for biomarkers. Survival status and clinical response (CR, PR, SD, PD) will be also documented.

• Study Type: Observational
• Enrollment (Actual): 30

Contacts and Locations

Study Locations

• Greece
  • Alexandroupolis
    • Alexandroupoli, Alexandroupolis, Greece, 68100
      • University General Hospital of Alexandroupoli
  • Attica
    • Athens, Attica, Greece, 11528
      • Aretaieio University Hospital of Athens
    • Athens, Attica, Greece, 124 62
      • University General Hospital of Athens Attikon
  • Piraeus
    • Piraeus, Piraeus, Greece, 18547
      • Metropolital Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

120 with metastatic breast cancer 30 healthy subjects

Description

Inclusion Criteria:

1. Female aged ≥ 18 years of age.
2. Histological confirmed ER+/HER2- metastatic Breast Cancer prior to beginning a treatment
3. Life expectancy permits participation to the study.
4. Available tumor tissue sample for molecular analysis.
5. Signed informed consent form.

Exclusion Criteria:

1. Female younger than 18 years old.
2. History of another malignancy within 3 years or current 2nd primary malignancy.
3. Patients that have not signed the informed consent.

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Metastatic Breast Cancer; The study population are subjects with a confirmed diagnosis of ER+/HER2 metastatic Breast Cancer patient before the treatment initiation. The selected inclusion/exclusion criteria have been set to include in the performance study appropriate population of interest, as broad as possible, but to exclude these subjects that have another current malignancy or any history of recent malignancy within 3 years.	Diagnostic test: PIK3CA kit; Prospective investigation of clinical samples for evaluation of IVD clinical performance
Healthy volunteers; In case of healthy volunteers only peripheral blood samples will be collected.	Diagnostic test: PIK3CA kit; Prospective investigation of clinical samples for evaluation of IVD clinical performance

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical performance of PIK3CA kit in CTCs, plasma and tumor tissue samples of metastatic breast cancer patients	The performance of PIK3CA kit on detecting mutations in CTCs samples of metastatic breast cancer patients will be assessed via Sensitivity, Specificity, Positive and Negative Predictive Values, Positive and Negative Likelihood Ratios, Accuracy and Diagnostic Odds Ratio. The point of primary evaluation in CTCs samples will be at baseline and droplet digital PCR will be used as reference method. The performance of PIK3CA kit on detecting mutations in plasma-ctDNA, and tumor tissue samples of metastatic breast cancer patients will be assessed via Sensitivity, Specificity Positive and Negative Predictive Values, Positive and Negative Likelihood Ratios, Accuracy and Diagnostic Odds Ratio. The point of primary evaluation in plasma-ctDNA and tumor tissue samples will be at baseline and therascreen PIK3CA RGQ PCR Kit will be used as reference method.	18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
- To study the PIK3CA Mutation Status before and after treatment of metastatic breast cancer patients using PIK3CA kit.	Presence of PIK3CA mutations at a second visit following to baseline of metastatic breast cancer patients using the PIK3CA kit.	24 months
- To assess the PIK3CA Mutation Status before treatment vs treatment response of metastatic breast cancer patients using PIK3CA kit.	Association of PIK3CA mutations presence at baseline with clinical response to treatment (CR, PR, SD, PD) of metastatic breast cancer patients using PIK3CA kit.	24 months
- To correlate patients' survival status with PIK3CA mutations at baseline	Metastatic breast cancer patients' survival status by presence of PIK3CA mutations at baseline.	24 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
To study CK-19 expression in CTC samples	Detection of CK-19 expression in CTCs	24 months
To study methylation status of ESR1 in CTC, ctDNA and tumor tissue samples	Methylation status of ESR1 in CTC, plasma and tumor samples	24 months
To study the presence of other biomarkers in tissue and liquid biopsy sample (at baseline).	Molecular profile of cancer biomarkers between tissue and peripheral blood samples	24 months

Collaborators and Investigators

• Sponsor: Pharmassist Ltd
• Collaborators: University of Athens

Study record dates

Study Major Dates

• Study Start (Actual): October 11, 2019
• Primary Completion (Actual): February 8, 2022
• Study Completion (Actual): February 8, 2022

Study Registration Dates

• First Submitted: February 20, 2020
• First Submitted That Met QC Criteria: July 20, 2020
• First Posted (Actual): July 21, 2020

Study Record Updates

• Last Update Posted (Actual): December 30, 2025
• Last Update Submitted That Met QC Criteria: December 23, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: PIK3CA; Liquid biopsy; Plasma; CTC
• Additional Relevant MeSH Terms: Nervous System Diseases; Neoplasms by Site; Neoplasms; Neuromuscular Diseases; Genetic Diseases, Inborn; Peripheral Nervous System Diseases; Neurodegenerative Diseases; Skin Diseases; Breast Diseases; Congenital Abnormalities; Heredodegenerative Disorders, Nervous System; Nervous System Malformations; Polyneuropathies; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Skin and Connective Tissue Diseases; Breast Neoplasms; Hereditary Sensory and Autonomic Neuropathies
• Other Study ID Numbers: CBS-PIK3CA

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No