by Robert Petcavich, MS, Ph.D, PMD. | Executive View | December 10, 2025
A New Shift in Healthcare Is Beginning
Every significant advance in technology begins with a discovery that changes our understanding of what can be measured, modeled, or controlled.
The semiconductor originated as a physics experiment.
Genome sequencing began as an academic exercise with limited practical expectation.
The GPU was designed for graphics long before it became integral to modern artificial intelligence.
In each instance, progress occurred because new methods of processing information made previously inaccessible insights available.
Nanophotonics occupies a similar position today. It sits at the intersection of physics, computation, and molecular biology, yet its implications are far-reaching. It offers the possibility of addressing one of the most consequential challenges in healthcare: detecting cancer at its earliest and most treatable stages.
This is not speculation.
It is a recognition of what physics makes possible.
Throughout the history of medicine, major diagnostic breakthroughs from X-rays to MRI to genome sequencing began as advances in measuring physical signals. Nanophotonics has the potential to follow the same trajectory, providing a new means of observing biological change long before conventional tools can detect it.
The Universal Human Truths
Everyone of us carries roughly 30 trillion cells, and billions of them divide each day. Most of the time, the process works perfectly, but occasionally a mistake slips through. When the cell cannot repair that mistake, it becomes the first step toward cancer.
Under normal conditions, a cell functions within a tightly regulated environment. Multiple checkpoints instruct it to pause division, repair damaged DNA, or initiate programmed cell death if the damage cannot be resolved. When a cancer-initiating mutation disables one of these controls, the cell begins to operate outside the regulatory framework that maintains tissue integrity. It divides when it should not and no longer participates in the cooperative behavior required for healthy function.
Healthy tissue depends on adherence to a set of shared rules. Cells stop growing when space is limited, remain within defined boundaries, and communicate with neighbors to maintain structural organization. As malignant transformation progresses, these constraints erode. Cancer cells expand despite crowding, infiltrate adjacent tissue, detach from their point of origin, and disregard regulatory signals from the body.
The limitation in our current approach to cancer is not the lack of effective treatments. Therapeutic options have advanced significantly. The challenge is that cancer is often detected only after these early deviations have developed into more established disease. These initial events occur at a molecular level long before conventional tools are capable of recognizing them, and by the time the disease becomes detectable, valuable time has already been lost.
Our diagnostic methods depend on signals that arise only after cancer has matured. Imaging and ctDNA are valuable modalities, but both rely on consequences rather than early molecular change. Imaging detects cancer only when there is sufficient structural alteration to register as a mass or density difference. A cluster of a few thousand abnormal cells produces no measurable shadow and no meaningful effect on the physics of X-rays or ultrasound. The disease must accumulate mass, reorganize the surrounding tissue, and reach a detectable threshold. By that point, it may be far beyond its earliest stage.
ctDNA operates on a related principle, but from a biochemical standpoint. It does not identify early malignant behavior; it identifies debris. For tumor DNA to appear in circulation, the cancer must be large enough and stressed enough to undergo cell death, rupture, and leakage. It must form disordered blood vessels and shed components into the bloodstream. Extensive evidence shows that early-stage tumors, particularly Stage 0 and Stage I, do not shed enough DNA to be measured reliably, even with the most sensitive sequencing technologies.
Early Metabolic Rewiring
One of the earliest and most consistent features of malignant transformation is a shift in cellular metabolism. Even before a tumor becomes anatomically detectable, cancer cells begin altering the way they acquire and utilize energy. These changes are not incidental. They are required to support continuous proliferation and the biosynthetic demands of building new cellular components for rapid cancer growth.
To accomplish this, early cancer cells send signals that influence how nutrients are processed in their immediate environment. They increase glucose uptake to fuel glycolysis, a rapid but inefficient energy pathway that supports accelerated growth. They draw in greater quantities of amino acids to sustain protein synthesis. They also increase lipid acquisition and synthesis, since lipids are essential for constructing new membranes as the cells divide.
These metabolic demands extend beyond the individual cell. They influence neighboring cells and reshape local nutrient gradients. The result is a microenvironment in which resources are redistributed to favor abnormal growth. Although these changes are not yet systemic and remain below the detection threshold of circulating biomarkers, they produce measurable shifts in the biochemical composition of the tissue.
From a physical standpoint, altered metabolism changes the concentrations, structures, and interactions of biomolecules. This affects their vibrational properties and the way they absorb and scatter light. These early biochemical deviations, while invisible to anatomical imaging and insufficient to generate ctDNA, nonetheless create distinct physical signatures that nanophotonic sensing can detect.
Toward a New Standard for Early Detection
For decades, our diagnostic tools have been constrained by biological visibility. Imaging requires a mass large enough to distort anatomy. Genomic assays require enough cell death to release detectable DNA. Both approaches reveal cancer only after the disease has advanced beyond its earliest and most treatable state.
Nanophotonics offers a different path. By detecting the physical consequences of early metabolic and biochemical change, it provides access to information that biology does not yet express. When combined with computation and grounded in biological understanding, it becomes possible to define the onset of disease not by the appearance of a tumor, but by the first measurable deviation in molecular behavior.
This shift carries significant implications. Earlier detection means less invasive treatment, fewer systemic therapies, and a higher likelihood of cure. It also offers a more accurate understanding of how cancer begins, progresses, and interacts with its environment. In the long term, recognizing disease at its physical origin rather than its visible form has the potential to reshape screening paradigms, clinical workflows, and patient outcomes on a broad scale.
We are at the threshold of this transition. The foundational physics is established, the computational tools are capable, and the biological framework is increasingly well understood. What remains is to integrate these elements into a coherent diagnostic architecture that can be deployed reliably and at scale.
The goal is straightforward. Detect cancer at the cellular molecular level before it comes visible at the macro level scale when it’s too late. Identify disease by the earliest measurable change, not by its structural consequences. Use physics to reveal what biology conceals, and use computation to interpret what physics uncovers.
If we can do this, early detection becomes not a matter of chance, but a matter of design. Cancer is a race against time, and nanophotonics may simply allow us to begin earlier.
About the author
Robert Petcavich, MS, Ph.D., PMD, is a physicist, materials scientist, and technology innovator whose career spans more than four decades across semiconductors, photonics, medical devices, and diagnostic platform development. His work focuses on using physical science to solve biologically complex problems, including the early detection of disease. He has served as a founder, inventor, and senior technology executive at companies advancing next-generation sensing systems, nanomaterials, and analytical instrumentation. Dr. Petcavich is known for translating foundational principles in physics into practical tools for healthcare and industry, holding patents across optical materials, surface chemistry, and signal-processing technologies. Dr. Petcavich has 53 issued US patents and over 100 published and granted internationally.
