I have seen this a number of times. Maybe not the exact same, but similar. A few times with formal disgnosis of esophagitis, a few without. We treated for both (steroids for esophagitis and fluc for thrush ; unclear which was the chicken or the egg…or if one predisposes to the other. In all patients they respond very quickly to antifungal Rx. and A TEMPORARY hold of Rx.
I suspect that the inflammation is worse in pts receiving checkpoints just because the immune system is so primed and ready and therefore the slightest insult leads to significant inflammation.
Let us know how your patient does.