Pathology testing device may improve bedside cancer diagnosis
Scientists at Harvard Medical School may be close to perfecting a device that can allow oncologists to diagnose cancer at a patient’s bedside in less than 60 minutes, according to an article published in Technology Review.

The heart of this technology is a new microchip that interacts with smartphone software.

Engineered by scientists at Harvard Medical School and Massachusetts General Hospital in Boston, the portable nuclear magnetic resonance (micro-NMR) system analyzes small tissue samples. This system accurately identifies malignancies 96 percent of the time, which, according to researchers, is more accurate than the existing cancer tests used by pathology and clinical laboratories.

Hakho Lee, PhD, one of the study’s authors and an assistant professor at the Center for Systems Biology at Massachusetts General Hospital, suggested that removing the possibility for human error might explain the micro-NMR test’s accuracy.

As described by Lee, the standard procedure now in use requires a physician to send a patient’s tissue biopsy to a lab. There the tissue is processed in the histology laboratory, then mounted on slides and analyzed by surgical pathologists. However, Lee noted that this workflow can introduce proteins not present in the original tissue sample. By contrast, the new micro-NMR test bypasses that entire anatomic laboratory process.

According to the final report by the study authors, the mean clinical turnaround time for conventional pathology, from sample submission to final report, was three days for cytology (range, one to eight days) and four days for surgical pathology (range, one to 11 days). The measurement time for micro-NMR was typically less than 60 minutes.

The micro-NMR system can simultaneously detect proteins from multiple types of cancers. To do this, researchers developed a microchip that holds magnetic nanoparticles in a solution. Binding molecules, or ligands, are then attached to the nanoparticles. When tissue samples from patients are injected into the microchip, the system generates a magnetic field through which the smartphone-based software identifies which proteins have attached to which ligands. This enables the device to then deliver a positive or negative result for specific cancer types.

Researchers discovered, however, that the proteins degraded quickly after about an hour, leading them to conclude that for the test to be successful, the sample proteins would have to be fixed on the cell surface, or the test would have to be concluded within the one-hour window. The researchers opted for the latter. They designed the micro-NMR chip to install on a smartphone, enabling physicians to analyze the sample and render a diagnosis at the patient’s bedside in less than 60 minutes.

Micro-NMR’s first application will be used to diagnose tuberculosis. The research group’s next project involves using the system to detect ovarian cancer.