Rotting leaves on new dendrobium cane

[tjselwyn]

For some reason the leaves on one of the new canes on this dendrobium are rotting; the plant is otherwise healthy, including a second, smaller new cane. Presumably the rot means this cane is a loss, but I don't know what to do about it. Should I remove the whole cane to prevent any rot spreading, or perhaps just the leaves? Or let it be for a little while and see what happens?