Deleting First Names From Artist Tag

I'm wondering if someone could help me with this. I don't even know if it's possible but here it goes. I have artist tags with first and last names such as:

First Last, First Last, First Last & First Last

I am trying to make an action that would check if there is a comma in the artist tag and then get rid of all the first names so that it will be left with:

Last, Last, Last & Last

In this example there were 4 artists but there could any number of artists using the same comma separated format with the last artist being separated with an ampersand. Thanks in advance.

Find inspiration there ...
/t/14169/1

ARTIST_NEW <== $regexp(%ARTIST%,'([^ &,]+)\s([^ &,]+)','$2')

From ... ARTIST = "Bing Crosby, Grace Kelly, Tim & Struppi & The Rolling Stones"
To ... ARTIST_NEW = "Crosby, Kelly, Tim & Struppi & Rolling Stones"

DD.20170819.1055.CEST

Apart from the intellectual challenge: what does an actual use case look like?

Modify "Herbert von Karajan & Berliner Philharmoniker" to "von Karajan & Philharmoniker"?
Go from "Johnny Clegg & Savuka" to "Clegg & Savuka"?
"Diana Ross & The Supremes & The Temptations" to "Ross & Supremes & Temptations"?

That does not really look right to me.

Thanks for that. I'll try it out and see how it goes.

This is not so much for the tag itself but the filename. I'm trying to shorten the filenames of classical tracks but the actual artist tag will have the complete names.