Is it possible to eliminate message conversations from my profile?

Literally that. I can't find a way to do it.

Somebody sent a PM to 40+ people promoting themselves, I suspect that the mods have already gotten words of it since the sender account is now deleted. Problem is now I'm stuck with this conversation that gives me message notification when anybody sends a reply.

There isn't for you; the best thing to do is to report it to the staff and we can make it go away (I just did).

We actually weren't aware of this person until now; their account was deleted because they deleted it themselves.

Ok, thanks for the info and the help

Maybe in the future an ‘ignore’ button could be added, like in the forum, so no replies in an e-mail thread don’t count towards notifications?