It's better to be converted to make use of it in Dynamo.
It's more like imitating than converting. Gather information from topo mesh, and create a Polysurface which has the same shape from it.
Above will give you a Polysurface from given Topography.
If you want to make your Dynamo graph simpler, use bottom.
After convert it, you can do a lot of things with it.
These are my Dynamo practices involved with Revit Topography.
1. Cut Volume Generator
I know cut volume can be reported by using Graded Region. My dyn generates a cut volume as a 3D geometry with 45 degree cut slope automatically from topography which has several pads.
2. Model Line To Contour
It makes Topography from selected model lines which are at the same level.
I've been imagined this feature should be included as one of original features in Revit. And I have one.:)
3. Contour Smoother
Maybe, it's not a new feature if you have the new site-tool of Revit 2015.
You can download above definitions as usual.