So sorry you're finding this. There is real lack of education and concern on the part of all doctors (cancer centers and doctors outside that field) about the real concerns for lymphedema post lymph node removal. Kathy Bates, the actress, developed pretty severe lymphedema with her breast surgery and is a big advocate for the concerns you raise.

I developed lymphedema on my left side from the removal of ONE LYMPH NODE.....yup, just one. There was significant damage during surgery trying to remove it. It wasn't even the side where I had the invasive cancer. So, it's quite possible to develop lymphedema from even one node...although my doctors wouldn't allow me to go to lymphedema classes so I had to get the information myself prior to surgery. They said that the chances of developing lymphedema in my case was just not possible (these are my oncologists and surgeons). Surprise.....a year later and a year of complaining from me and my paying for massage therapy and physical therapy myself, the doctors admitted I indeed had lymphedema. I was lucky because a follow up surgery pretty much erased the damage and my lymphedema is well controlled.
I have to advocate for myself at each and every blood draw and blood pressure reading in asking that they use only my right arm (lymphedema on the left).......bi lateral mastectomy. I can't imagine if I had to request the blood draws elsewhere......Hugs