From: Return to Planet Hulk Part V.
Amadeus Cho is in self exile in deep space wen he gets a distress call from Sakaar. When his ship lands on the planet surface, he is captured and forced to fight in a gladiatorial arena by the evil despot known as The Warlord of Sakaar.
In the climactic battle between the two, the warlord unleashes his version of a worldbreaker, a Cold War era tactical nuke (how he got it is not explained) and drops right on top of the jade giants pointy coif.
We know that the Hulk can absorb nuclear energy, but so far the upper limits have not really been shown yet. My hypothesis is that the angrier he is the more he can absorb and you can see here, he was pretty angry…