Breast NeoplasmsFATLASNCT04200768
FATLAS: Comprehensive Multi-level Characterization of Systemic and Mammary Adiposity in Breast Cancer Patients.
A study testing Prospective data and sample collection in people with Breast Neoplasms, run by Universitaire Ziekenhuizen KU Leuven at 1 site in Belgium.
Trial summary
FATLAS is a prospective, interventional, non Investigational Medicinal Product (IMP) study aiming to characterize the micro- and macroenvironment of breast cancer according to patient adiposity in different histological and molecular subtypes. Read more about this study
- Who is it for?
- Ages 18 to 75 yearsHealthy volunteers can take part
- Conditions the study is for
- Breast Neoplasms
- What is being tested?
- Prospective data and sample collection
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 150 participants
- Where
- 1 siteBelgium
- Study dates
- 1 Sep 2020to 31 Oct 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Inclusion of 30 lean (BMI 18.5 - 24.9 kg/m²), 30 overweight (BMI 25 - 29.9 kg/m²), and 30 obese (BMI ≥ 30 kg/m²) patients with histological confirmation of Invasive Ductal Carcinoma (IDC) on core diagnostic biopsy; 5 lean, 5 overweight and 5 obese Inflammatory Breast Cancer (IBC) patients; 15 lean, 15 overweight and 15 obese patients with histological confirmation of Invasive Lobular Carcinoma (ILC) on core diagnostic biopsy and 20 male subjects with any type of breast cancer that meet following criteria:
- be willing and able to provide written informed consent for this study;
- be willing to provide plasma/blood and tissue samples;
- be willing to have clinical measures of adiposity taken;
- have stage I, II or III disease (so non-metastatic) with any clinical lymph node status;
- be scheduled for surgical resection of the tumour in UZ Leuven.
- have a tumour size of ≥ 1.5 cm in order to have sufficient tumour material for the biomarker analysis. Exceptions will be made for IBC patients, as in some cases no residual tumour will be found after neoadjuvant treatment;
- be treatment naïve, i.e. not having received systemic breast cancer treatment prior to surgery. An exception is made for the IBC patients, as they will often have received first line neoadjuvant chemotherapy before surgery. IBC patients that do not undergo surgery after neoadjuvant treatment (e.g. because of inoperability of the patient) will not be included;
Who cannot join
- pregnancy at time of diagnosis;
- personal history of breast cancer (relapse/second primary);
- mixed invasive tumour type on core biopsy or special type of breast carcinoma beside pure ILC;
- history of an additional malignancy that is progressing or that has required active treatment in the 5 years prior to breast cancer diagnosis. Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the skin that have undergone potentially curative therapy or in situ cervical cancer;
- presence of an immune dysregulatory disease or condition which requires active immune modulatory treatment of any kind, or has required treatment in the past two years. Replacement therapy (e.g., thyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment;
- history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial in the opinion of the treating investigator.
Trial locations and contacts
1 site in 1 country.
About this study
FATLAS is a prospective, interventional, non Investigational Medicinal Product (IMP) study aiming to characterize the micro- and macroenvironment of breast cancer according to patient adiposity in different histological and molecular subtypes.
The macroscopic profiling of the patient's adiposity will be based on Body Mass Index (BMI), bioimpedance analysis and waist-to-hip ratio. Blood samples will be taken for lipidomic analyses and for hormonal and immuno assays. Microscopic profiling of adiposity and inflammation will be done on fresh frozen (FF) and Formalin-Fixed Paraffin-Embedded (FFPE) samples from the tumour resection specimen and will consist of histological characterization, immuno assays, multiplex immunohistochemistry, DNA sequencing and single nuclei RNA sequencing both in the tumour and in adjacent normal mammary tissue.
- Conditions
- Breast Neoplasms
- Being tested
- Prospective data and sample collection
- Keywords
- Breast Cancer, Body Mass Index, Adiposity, Obesity, Inflammatory Breast Cancer, Lobular Breast Cancer, Tumour Microenvironment
- Medical subject headings
- Breast Neoplasms, Obesity, Inflammatory Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Prospective data and sample collectionOther
Performance of measurements of adiposity, extra collection of blood samples
| Study group | Role | What they receive |
|---|---|---|
| Standard | Other | Standard of care Receives: Other: Prospective data and sample collection |
What is being measured
The primary outcome is the main question the study is designed to answer.
BMI
Calculated: body mass (kg) divided by height squared (m²)
Measured: Before surgery
Lipid levels in plasma
Lipidomic analysis
Measured: Before surgery
Up- or downregulation of pathways on single cell level
Single nucleus RNA sequencing using 10X Genomics Platform after dissociation of tissue into single nuclei
Measured: At surgery
T cell repertoire
Number of T-cells per population using immunohistochemical phenotypic markers of cell type and of exhaustion.
Measured: At surgery
Physical activity level
Time of activity of different intensities and time of sedentarity, evaluated using the Global Physical Activity Questionnaire (GPAQ) of the World Health Organisation (WHO) (scale: minutes per day, range [0 - 1440]). The higher the score for activity the better, the lower the score for sedentarity the better.
Measured: Before surgery
Sleep behaviour score
Pittsburgh Sleep Quality Index (PSQI) score (range: [0 - 21]). Higher scores indicate worse sleep quality.
Measured: Before surgery
Dietary Quality Index
Nutritional score (natural number, range [0 - 100]) calculated using the in-house Food Frequency Questionnaire. A score of > 70 indicates healthy dietary behaviour.
Measured: Before surgery
Dietary Food Intake
Food intake in kcal per day calculated using the in-house Food Frequency Questionnaire.
Measured: Before surgery
Fat percentage
Calculated from multiple frequency bio-impedance measurements (in %, range [0 - 100]).
Measured: Before surgery
Waist-to-hip ratio
Waist circumference (cm) divided by hip circumference (cm)
Measured: Before surgery
Handgrip strength
In kilograms (kg), measured by handheld dynamometer.
Measured: Before surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Dec 2019
- Study start1 Sep 2020
- Primary completion31 Oct 2028 (estimated)
- Study completion31 Oct 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Breast NeoplasmsStudies of the same condition, open and under way.
- More trials run by Universitaire Ziekenhuizen KU LeuvenThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 150 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universitaire Ziekenhuizen KU Leuven
- Sponsor type
- University, hospital or other
- Collaborators
- KU Leuven
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04200768
- Sponsor's protocol ID
- S63330
- Acronym
- FATLAS
- Status last verified
- May 2026
- First submitted
- 21 Nov 2019
- Last updated
- 18 May 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- FATLAS: Comprehensive Multi-level Characterization of Systemic and Mammary Adiposity in Breast Cancer Patients.
- ClinicalTrials.gov ID
- NCT04200768
- Acronym / sponsor ID
- FATLAS / S63330
- Conditions
- Breast Neoplasms
- Keywords
- Breast Cancer, Body Mass Index, Adiposity, Obesity, Inflammatory Breast Cancer, Lobular Breast Cancer, Tumour Microenvironment
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 150 participants (estimated)
- Lead sponsor
- Universitaire Ziekenhuizen KU LeuvenUniversity, hospital or other
- Collaborators
- KU Leuven
- Study start
- 1 Sep 2020 (actual)
- Primary completion
- 31 Oct 2028 (estimated)
- Study completion
- 31 Oct 2028 (estimated)
- First posted
- 16 Dec 2019 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
FATLAS is a prospective, interventional, non Investigational Medicinal Product (IMP) study aiming to characterize the micro- and macroenvironment of breast cancer according to patient adiposity in different histological and molecular subtypes.
The macroscopic profiling of the patient's adiposity will be based on Body Mass Index (BMI), bioimpedance analysis and waist-to-hip ratio. Blood samples will be taken for lipidomic analyses and for hormonal and immuno assays. Microscopic profiling of adiposity and inflammation will be done on fresh frozen (FF) and Formalin-Fixed Paraffin-Embedded (FFPE) samples from the tumour resection specimen and will consist of histological characterization, immuno assays, multiplex immunohistochemistry, DNA sequencing and single nuclei RNA sequencing both in the tumour and in adjacent normal mammary tissue.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Standard | Other | Other: Prospective data and sample collectionStandard of care |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Inclusion of 30 lean (BMI 18.5 - 24.9 kg/m²), 30 overweight (BMI 25 - 29.9 kg/m²), and 30 obese (BMI ≥ 30 kg/m²) patients with histological confirmation of Invasive Ductal Carcinoma (IDC) on core diagnostic biopsy; 5 lean, 5 overweight and 5 obese Inflammatory Breast Cancer (IBC) patients; 15 lean, 15 overweight and 15 obese patients with histological confirmation of Invasive Lobular Carcinoma (ILC) on core diagnostic biopsy and 20 male subjects with any type of breast cancer that meet following criteria:
- be willing and able to provide written informed consent for this study;
- be willing to provide plasma/blood and tissue samples;
- be willing to have clinical measures of adiposity taken;
- have stage I, II or III disease (so non-metastatic) with any clinical lymph node status;
Key exclusion criteria (6 listed)
- pregnancy at time of diagnosis;
- personal history of breast cancer (relapse/second primary);
- mixed invasive tumour type on core biopsy or special type of breast carcinoma beside pure ILC;
- history of an additional malignancy that is progressing or that has required active treatment in the 5 years prior to breast cancer diagnosis. Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the skin that have undergone potentially curative therapy or in situ cervical cancer;
- presence of an immune dysregulatory disease or condition which requires active immune modulatory treatment of any kind, or has required treatment in the past two years. Replacement therapy (e.g., thyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Prospective data and sample collectionPerformance of measurements of adiposity, extra collection of blood samples | Other | Standard |
Primary outcome
BMI
Time frame: Before surgery
Calculated: body mass (kg) divided by height squared (m²)
Lipid levels in plasma
Time frame: Before surgery
Lipidomic analysis
Up- or downregulation of pathways on single cell level
Time frame: At surgery
Single nucleus RNA sequencing using 10X Genomics Platform after dissociation of tissue into single nuclei
T cell repertoire
Time frame: At surgery
Number of T-cells per population using immunohistochemical phenotypic markers of cell type and of exhaustion.
Physical activity level
Time frame: Before surgery
Time of activity of different intensities and time of sedentarity, evaluated using the Global Physical Activity Questionnaire (GPAQ) of the World Health Organisation (WHO) (scale: minutes per day, range [0 - 1440]). The higher the score for activity the better, the lower the score for sedentarity the better.
Sleep behaviour score
Time frame: Before surgery
Pittsburgh Sleep Quality Index (PSQI) score (range: [0 - 21]). Higher scores indicate worse sleep quality.
Dietary Quality Index
Time frame: Before surgery
Nutritional score (natural number, range [0 - 100]) calculated using the in-house Food Frequency Questionnaire. A score of > 70 indicates healthy dietary behaviour.
Dietary Food Intake
Time frame: Before surgery
Food intake in kcal per day calculated using the in-house Food Frequency Questionnaire.
Fat percentage
Time frame: Before surgery
Calculated from multiple frequency bio-impedance measurements (in %, range [0 - 100]).
Waist-to-hip ratio
Time frame: Before surgery
Waist circumference (cm) divided by hip circumference (cm)
Handgrip strength
Time frame: Before surgery
In kilograms (kg), measured by handheld dynamometer.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 May 2026.
- Individual participant dataSharing planned: No
Related trials for Breast Neoplasms
Active, not recruiting
Streamlined Geriatric and Oncological Evaluation Based On IC Technology
Breast Cancer, Comorbidities and Coexisting Conditions
RecruitingPhase 2
Gene Signatures to Guide HR+MBC Therapy in a Diverse Cohort
Invasive Mammary Carcinoma, Metastatic Breast Cancer
Not yet recruitingObservational study
Comparison of Reliability, Time Cost, and Participant Comfort of Lymphedema Assessments in Upper Extremity
Lymphedema, Upper Extremity Lymphedema
RecruitingPhase 3
A Study of Camrelizumab Plus Chemotherapy in Combination With or Without Famitinib as Neoadjuvant Therapy in Participants With Triple Negative Breast Cancer (BCTOP-T-N01)
TNBC - Triple-Negative Breast Cancer
RecruitingPhase 3
Testing Whether Hormone Therapy With Ribociclib is as Effective as Chemotherapy Followed by Hormone Therapy With Ribociclib for the Treatment of High Anatomic Stage Breast Cancer With Low Recurrence Risk, The RxFINE-Low Trial
Anatomic Stage II Breast Cancer AJCC v8, Anatomic Stage IIIA Breast Cancer AJCC v8
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Prospective data and sample collection in people with Breast Neoplasms, run by Universitaire Ziekenhuizen KU Leuven at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 18 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
BMI (time frame: Before surgery). The study lists 11 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 May 2026.