I'll see if I can find a simple package for you to get started on in the
mean time. Mario, Sébastien, would you have a simple package for
Alexandre to begin working on?

I have had a look at 3D Slicer, and its build instructions seem well documented (though the build process is quite slow):

Perhaps this would be an interesting project? There is also medInria and Icy:

As far as Orthanc is concerned, I am working on a development package and on a FUSE filesystem, but it is still WIP (expect nothing before, say, November). Maybe you could also help Mario in porting the Orthanc package to RHEL and CentOS via EPEL?

Just my two pennies worth...