The history of medicine is a progression shaped by discoveries, instruments, and conceptual advances that have profoundly transformed our understanding of disease. For centuries, physicians grounded their diagnostic assessments primarily in their senses: the inspection of the skin, the auscultation of the thorax, the palpation of internal organs. The human body was interpreted through what could be directly perceived.
From Perception to Measurement
A major transformation occurred between the eighteenth and nineteenth centuries, when medicine began to measure what previously could only be inferred. The introduction of the thermometer, the sphygmomanometer, and the stethoscope made it possible to convert sensory impressions into numerical data, rendering diagnosis less subjective and more reliable.
Shortly thereafter, microscopy opened a new horizon: no longer merely the body, but its tissues and cells became the focus of scientific observation. This marked the birth of laboratory medicine.
The nineteenth and twentieth centuries brought further revolutions: from X-rays to ultrasound imaging, from CT scans to the first chemical analyses of blood, such as glucose and creatinine testing. At the same time, clinical laboratories introduced standards and protocols that made these measurements reproducible, precise, and universally recognized.
Biomarkers and Precision Medicine
The last two decades have marked a further evolutionary leap: the advent of precision medicine, which investigates what differentiates one individual from another and one disease from another.
Within this context, the concept of the biomarker has taken shape. A biomarker is a measurable biological characteristic (a protein, a molecule, a gene, a metabolite) that provides information about physiological processes, pathological conditions, or responses to treatments.
In other words, it is a signal emitted by the body—one that can be analyzed to determine whether everything is functioning as it should or whether something is beginning to change.
What Are Biomarkers Used For?
Early diagnosis: they detect biological alterations before symptoms appear.
Prognosis: they help predict the course of a disease.
Monitoring: they track the progression of a condition over time.
Therapeutic assessment: they measure the response to treatments in order to tailor therapy.
Prevention: they identify individuals at risk and enable more timely interventions.
Their value is not merely diagnostic but strategic: they are essential tools for a form of medicine that is increasingly predictive and personalized.
What Types of Biomarkers Exist?
Proteins: among the most common; they change rapidly in response to physiological or pathological processes.
DNA: mutations, variants, or epigenetic signals can indicate predispositions or disease states.
RNA: such as microRNAs, which undergo highly specific modifications in different pathologies.
Metabolites: small molecules derived from cellular metabolism that serve as indicators of systemic dysfunctions. Among these are VOCs (Volatile Organic Compounds), volatile organic compounds found in human breath—one of the new frontiers of non-invasive diagnostics.
VOCs and Breath as a New Source of Information
VOCs, among the most innovative classes of biomarkers, are particularly compelling because they enable the analysis of metabolism in a simple and non-invasive manner.
