Meta Data - HELP!!

Hi there,
I've got some Meta Data questions that I'm hoping someone has some answers for:
A) Can an existing IPTC Scene have it's name changed?
B) Can an existing IPTC Scene be cleared out of a group of images?
C) Can an existing IPTC Scene be deleted easily across a multitude of images?

Over the past year I've created a bunch of scenes, and the list has gotten too cumbersome. I'd like to reduce them down. I've noticed that multiple scenes can be added to an image, unlike many of the other fields. This has created problems for me. Operator error for sure; but I'd love to find a solution.

Thanks,
Andrew