Exploring the Role of Serum Methylmalonic Acid (MMA) in Breast Cancer

Study Overview
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Brief Summary
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This project aims to investigate the role of MMA in breast cancer. To this end, we will measure MMA on serum samples collected at the time of breast cancer diagnosis, to investigate the role of MMA in predicting long-term recurrence risk, response to neoadjuvant chemotherapy, and its association with age and clinical frailty.

Detailed Description
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This project aims to investigate the role of MMA in breast cancer. To this end, we will measure MMA on serum samples collected at the time of breast cancer diagnosis, to investigate the role of MMA in predicting long-term recurrence risk, response to neoadjuvant chemotherapy, and its association with age and clinical frailty. If the role of baseline serum MMA in therapy resistance and/or metastasis is confirmed, our study could be further extended by evaluating SOX4 expression in the tumor tissues (SOX4 is activated by MMA, and SOX4 induces EMT (epithelial to mesenchymal transition) and the metastasis process.

Official Title
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A Retrospective Study Exploring the Role of Serum Methylmalonic Acid (MMA) in Breast Cancer---focusing on Metastasis, Chemotherapy Resistance, and Ageing Effects

Conditions
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Breast Cancer

Intervention / Treatment
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* Diagnostic Test: methylmalonic acid testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female patients older than 18 years at diagnosis. First diagnosis of invasive breast cancer. All pathological parameters are available to identify histological subtype according to standard procedures. Availability of frozen serum samples at diagnosis. Voluntarily signed Informed Consent obtained before blood drawing for biobanking was performed. Exclusion Criteria: Pregnant at diagnosis. stage 0 disease (in situ). Bilateral BC at diagnosis or multifocal unilateral BC with different histology. Other subtypes than Invasive ductal carcinoma. Prior breast cancer.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pri-Meta<br>patients with breast cancer metastasis at first diagnosis | Diagnostic Test: methylmalonic acid testing<br> <br> |
| Sec-Meta<br>patients with early breast cancer developed distant metastasis within 5 years | Diagnostic Test: methylmalonic acid testing<br> <br> |
| Non-Meta<br>patients with early breast cancer did not develop distant metastasis within 5 years | Diagnostic Test: methylmalonic acid testing<br> <br> |
| older<br>patients with breast cancer older than 70 years old with G8 screening | Diagnostic Test: methylmalonic acid testing<br> <br> |
| pCR<br>patients with breast cancer reached pCR after neoadjuvant chemotherapy | Diagnostic Test: methylmalonic acid testing<br> <br> |
| non-pCR<br>patients with breast cancer did not reach pCR after neoadjuvant chemotherapy | Diagnostic Test: methylmalonic acid testing<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| MMA levels | baseline serum MMA levels in pre-defined patients | baseline |