"We do often think of cancer as something that affects people who are older," Tegan said. "I think it's amazing to bring awareness to some of these cancers that are affecting young people."

They're also looking forward to checking out the night's stellar lineup, handpicked by Perry herself, which includes fellow female acts Sara Bareilles, Ellie Goulding and Kacey Musgraves. But, as the duo admitted, they're really just hoping Goulding hasn't forgotten about them.