Kris Jenner was supposed to be the guest of honor Wednesday night at DuJour Magazine's party in Miami Beach ... but she cancelled on them last minute.
The Art Basel bash is being thrown to celebrate Kris' cover debut for the magazine, but a rep for the party tells us she told them Tuesday night she won't be there. Our sources say Kanye's current medical situation was behind the cancellation.
We're also told Kourtney and Scott were supposed to show, but that's probably not happening.
The party will still have some names ... Kardashian BFF Larsa Pippen RSVP'd along with Martha Stewart and Nick Cannon.