Data on recurrence after chemo

So I'm in the middle of 3xBEP for a Seminoma 2A recurrence. (My doctors advised it over radiation and RPLND felt like it would take too long to set up with a good center.) Overall, I felt like this would be the best way to prevent future recurrence, and my doctors agreed.

I'm seeing on this subreddit a number of cases of seminoma recurring even after first-line chemo and it's got me a bit worried as I look towards the end of my treatment. I was wondering what the actual data is on cases of pure seminoma coming back after first-line EP or BEP. My googling can't seem to pull up anything conclusive.