A earlier topic that I posted a year or two ago; There was a commission meeting at Bari's Resteraunt. It included 4 families;

Huddled around Pizza ovens and Industrial mixing; You had

Anthony Corallo and Tom Mix Santoro - Lucchese
Paul Castellano and Joe Gallo - Gambino's
Jerry Langella and Donny Shacks - Colombo's
Vincent Gigante and Anthony Salerno - Genovese

The meeting got compromised by FBI and other LE tasks force but this is still the biggest meeting of the NYC families that i know about. I don't think anyone got arrested. They all managed to escape.