New imaging gives insight into tumours’ travels

Imaging of mouse lymph nodes, pictured here, gave scientists clues as to how cancer moves through the body Keystone

Through a high-resolution imaging system which makes lymph nodes highly visible, researchers from Zurich’s Federal Institute of Technology have come one step closer to understanding how cancer forms and travels through the body.

They found that a developing tumour blocks the lymphatic system’s normal paths, creating a sort of bypass. That discovery could help doctors spot and diagnose metastasising cancers earlier.

Cancer has long been known to stimulate the growth of blood and lymph vessels, but this is the first time it has been found to alter the circulation of the lymphatic system itself. Researchers made the discovery by injecting mice with a fluorescent substance and observing, under infrared light, how it travelled through the animal’s lymphatic system. Tiny details, down to the valves of blood vessels, were visible to scientists.

In humans, an oncologist would inject a coloured substance into a tumour and observe which lymphs take on the same colour, making it possible to spot the first signs of metastasising cancer. Michael Detmar, who directed the study, assured that the substance is not dangerous and simply passes through the body following the test.

The new method for viewing tumours is less complex than the current “positron emission tomography” test, which shows each organ in three dimensions. Scientists are already planning clinical trials to test their finding in humans.