Sorry for the "redo" on another diagnosis. That's no fun, I've been where you are twice when told I had it again. Once it was a recurrence, the second time it was a different primary. I just told myself it was no big deal, just another "inconvenience" for my daily life. I vowed I wouldn't let it change my daily schedule any more than absolutely had to. And I reassured myself by saying that I have done it twice before, I'll just do it again.
As far as your two being related, I cannot say. Doesn't seem like they would be. I asked the same question when I was dx'd the third time. I was convinced It had to be from the previous two. Who knows? I would bet the docs don't, at least they said they couldn't connect them.
Here is a link to both types of cancer on our diagnoses page, maybe you can get some info there.
Someone else should have some info for you soon.