Tumor in the Ultramicroscope, illuminated by the light sheet Credit: TU Wien

After cancer surgery, the crucial question is: Are there possibly cancer cells left behind that can continue to grow, or has the entire tumor actually been removed? To find out, the tumor is examined by pathologists. Until now, thin sections were made which were then analyzed under a microscope. A new technique, developed at TU Wien (Vienna), together with the TU Munich, could now initiate a revolution in pathology: Tumor tissue is made transparent and illuminated with a special ultramicroscope. This makes it possible to analyze all the