GMail allows you to recall a mail sent.
For about three seconds . . .
Honestly, if you are a major organization and still have, in this 3rd millenia, a mail server that blindly allows you to send CCs to more than a dozen mail addresses without a verification check or outright refusal without prior authorization, then I guess you have what you deserve.
It's been over a decade that we've all learned the hard way that Reply All should be practically banned, and sending mail to hundreds of external recipients at a time requires a process and overview that excludes any single operator.
But, as usual, the lesson still has to be learned the hard way.
Oh well, it's NHS. Par for the course, then. Carry on !