When you think of something already thought of

I recently finished CLOCKWORK ANGEL by Cassandra Clare.

In Clare's MORTAL INSTRUMENTS and INFERNAL DEVICES series, a treaty called the Accords is often mentioned. CLOCKWORK being the first of Clare's work that I had read, I was disappointed to learn of The Accords.

You see, my novel also features a peace treaty of sorts called the Accords.

Obviously, I didn't rip Ms. Clare off (I was inspired by the Camp David Accords, actually), but I wonder if her books being so popular means I need to rename my treaty? I'd prefer not to, but at the same time, I don't want readers unwittingly assuming I stole from one of their favorite authors.

I thought I'd throw this out there, since this is the second accidental similarity I have come across. You see, one of my betas pointed out that my novel and an already-published YA novel share a main character's nickname and last name. It's not like the character is Bella Swan, mind you, (I actually hadn't heard of the book until beta mentioned it) but still...

How do you handle accidental similarities between your WIP and an already-published novel? Do you change it? Bring it up with your agent (if you have one)? Leave it up to your (hopefully eventual) publisher to decide?