They most likely won't repeat tests but will want copies of everything. Usually sent ahead of time too. You can help him by keeping everything organized and even keep sort of a journal of who he saw when, what tests, etc.. We had my Dad's biopsy material sent to three different reputable cancer testing centers in the country to try and figure out exactly what cancer this started out as...
I can tell you that it is amazing how in charge of your own care you must be. Be aggressive - ask many questions. Have the doctors be specific "yeah I've seen Ampullary Cancer" Oh yeah? How many cases have you worked on specifically?
Hope this helps - lots of love,
Michelle