Hi @Caz1
I was told at the time that there can be as little as 10 or up to 50 in the axillary area. Everyone is different that's why they can't be too specific until they are out and sent to pathology. They took a fair size chunk of flesh out and there ended up being 24 nodes in there 5 with cancer that were breaking out into the surrounding area.
Personally I have had no problems with it at all. Still a bit numb right along the scar line but other than that, fully functional and strong as it ever was.
xoxoxo