The magnification given by the OP is something quite achievable with optics alone. It's roughly equivalent to a 2,000mm telephoto lens on an old 35mm film camera. Nikon first produced lenses like this decades ago.
Yes, they were big. So big, you mounted the lens on a tripod - and attached the camera, but part of the reason they were so big was so that they had a large collection area for light. In a medical setting, lighting is usually pretty darn good, so this isn't quite so demanding.
The other thing is that medical equipment is - quite consistently - up near, if not the, best that is available. Cost is less of an issue where lives are at stake - so the designers can opt for higher quality designs. Many years ago, I saw a macro zoom lens suitable for medical use, which had a ring flash around the lens for shadowless photography. The price was mind blowing - but so were the images.
You must traverse this optical path before you can enter the realm of image sensors and processing, but the state of the technology in that department does present a wonderful complement and incredible capability.