A group of researchers led by Angela Belcher, PhD, professor of biological engineering at MIT, has developed an imaging system that could be adapted to find tumors as small as a couple of hundred cells. Given the limitations in the current methods for imaging tumors, and the tradeoff between resolution and depth of imaging, an improved method to find tiny tumors deep within the body could revolutionize early cancer detection.
The imaging system, named DOLPHIN for “Detection of Optically Luminescent Probes using Hyperspectral and diffuse Imaging in Near-infrared,” is described in a paper in Scientific Reports titled, “Deep-tissue optical imaging of near cellular-sized features.”
“Our goal is to find tiny tumors, and do so in a noninvasive way,” says Belcher. Near-infrared light, which DOLPHIN relies on, is well suited to tissue imaging because long-wavelength light scatters less than does short-wavelength light when it strikes objects, allowing it to penetrate deeper into the tissue. Indeed, DOLPHIN demonstrated noninvasive real-time tracking of a 0.1-mm-sized fluorophore through the gastrointestinal tract of a living mouse and detected a signal to a tissue depth of 8 centimeters, far deeper than any existing imaging techniques.
The researchers note that this kind of system could be used with any fluorescent probe that emits light in the near-infrared spectrum, including some that are already FDA-approved. They hope to adapt their imaging technology for early diagnosis of ovarian cancer and other cancers that are currently difficult to detect until late stages.
“We want a way to follow recurrence of the tumors, and eventually a way to find and follow early tumors when they first go down the path to cancer or metastasis,” says Belcher. “This is one of the first steps along the way in terms of developing this technology.”