Blog
Disease biomarkers: a new era of precision medicine
What are biomarkers and why are they needed?
Biomarkers (or biological markers) are objective, measurable indicators that reflect the physiological or pathological state of the body. They can be detected in blood, urine, tissues, saliva, or other biological fluids. Biomarkers allow you to detect a disease at an early stage, predict its course, monitor the effectiveness of treatment, or even predict the risk of its development.
In modern medicine, biomarkers are the basis of a personalized approach, when decisions are made not only based on symptoms, but also on the biochemical data of a particular patient.
Biomarker classification
| Biomarker type | What does it show? | Examples |
|---|---|---|
| Diagnostic | Help establish a diagnosis | PSA (prostate cancer), Troponin (heart attack) |
| Prognostic | Predict the course or outcome of a disease | BRCA1/2 (risk of cancer), D-dimer (thrombosis) |
| Predictive | Show likely response to treatment | HER2 (response to targeted therapy) |
| Monitoring | Monitor treatment effectiveness or relapse | CEA, CA-125 (for oncology) |
| Screening | Used for mass testing of the population | glucose, cholesterol, Pap test |
Where are biomarkers most commonly used?
1. Oncology
PSA (prostate-specific antigen) — for the diagnosis and monitoring of prostate cancer
CA-125 — ovarian cancer marker
CEA (carcinoembryonic antigen) — for colorectal cancer
HER2 — for breast cancer to select therapy
KRAS, BRAF, EGFR — genetic markers to determine the effectiveness of targeted drugs
2. Cardiology
Troponin I and T — markers of myocardial damage (infarction)
BNP and NT-proBNP — in heart failure
LDL, HDL, CRP — to assess the risk of cardiovascular disease
3. Endocrinology
HbA1c (glycated hemoglobin) — long-term glucose control
TSH, T3, T4 — thyroid function markers
Insulin, C-peptide — assessment of pancreatic function
4. Infectious diseases
Procalcitonin — for the diagnosis of bacterial infection and sepsis
CRP (C-reactive protein) — nonspecific marker of inflammation
HBsAg, Anti-HCV — hepatitis B and C markers
Viral load (PCR) — HIV, COVID-19
5. Autoimmune diseases
Antibodies to ACCP, rheumatoid factor — with rheumatoid arthritis
ANA (antinuclear antibodies) — with systemic lupus erythematosus
Antibodies to TPO — with Hashimoto's thyroiditis
An example of the use of biomarkers in clinical practice
Situation:
A 46-year-old female patient presents with complaints of lower abdominal pain. Ultrasound reveals an ovarian neoplasm.
Biomarker:
The CA-125 level is 210 U/ml (normal is up to 35).
Decision:
Surgery is performed. After surgery, the marker level is used to monitor recurrence.
Advantages of biomarkers
Disease detection on early stages
Less invasive diagnostics
Help in determining the forecast disease
Possibility monitor the effectiveness of treatment
The basis for personalized therapy
Limitation
Not all biomarkers are specific: increase can occur in several different conditions
Doesn't always mean illness: for example, CA-125 is also elevated in endometriosis
Price of tests — some are quite expensive
Need correct interpretation by a doctor
Biomarkers of diseases are a tool that brings medicine closer to an individual approach. They allow not only to diagnose more accurately, but also to monitor the effectiveness of treatment, reduce the risks of complications and detect health threats in a timely manner. In the future, biomarkers will become the basis of personalized therapy for each patient.
