What determines if you need an RPLND?

So, I keep reading about something called an RPLND. I really don't want to have another surgery. What determines if you will need one? For those who have seen my previous posts, the tumor spread to my spine causing a compression, and i'm currently relearning to walk. It also spread to my right ilium hip bone causing a fracture. As a result, I had an emergency laminectomy and spinal fusion. While in the hospital, they did say it also spread to 2 lymph nodes but they said they will shrink after chemo. But it spread to nowhere else; no other organs. But based on what i'm seeing, the retroperitoneal lymph nodes are a group of several so I don't think they meant it was those. But I am reading that the pathology of the tumor also can determine an RPLND. Mine is a mixed germ cell of 80% yolk sac, 10% seminoma and 10% teratoma. I was told the amount of teratoma can affect this. I'm currently cycle 3 out of 4xBEP; my second "bleo only once" week starts on Monday and then my 4th cycle starts on the 9th. Any information on this is appreciated.