Plantgirl

I'm pretty sure your co-worker wasn't Catholic. We even have Patron Saints of Cancer, like St. Aldequndis, the Patron Saint of Breast Cancer who died of that cancer. (I first learned of her at a Komen Walk for the Cure blog) The Catholic party line is that the Saints certainly knew Jesus. Plus we have a generic Patron Saint of Cancer: St. Peregrine Laziosi
Finally, I know I'm wicked but I would share this video with your co worker. It's from CNN about an oral cancer patient who saw Jesus in her MRI. And I'd tell the co worker that Jesus was in my MRI also which means you plantgirl will be taken up in the rapture and your co worker is going straight to hell.
JESUS in my MRI

Keep the Faith
Charm