Hi Kenneth,
I would say yes, you can, it is a mesh so you will be working with vertices and faces. You can start by opening the file, going to grasshopper and with the “deconstruct mesh” and “deconstruct faces” nodes get the base data from your scanned object.
I have never done it, but you can, it may be a nightmare and ultraslow, so you may want to go from mesh to subd to polysurface first and work on the polysurface or subd and then mesh it again.
Cheers!