Well you see, I couldn’t swear, but I have seen cases where I thought or wondered whether or not there was a psychogenic reason for that particular ailment; it came too conveniently. Many things can be found out about cancer, I’m sure. ~Carl Jung, Evans Conversations, Page 34.

It is thought that cancer may be due to the later and anarchical development of embryonic cells folded away in the mature and differentiated tissues. ~Carl Jung, 1925 Seminar, Page 39.

I take his cancer to be a spontaneous growth, which originated in the part of the psyche that is not identical with consciousness. It appears as an autonomous function intruding upon consciousness. ~Carl Jung, CW 11, Para 21.

I’m terribly sorry X. has to suffer from cancer, in her case cancer really comes too early and it is a mean way of killing people anyhow. But nature is horrible in many respects. ~Carl Jung, Letters Vol. 1, Pages 437-438.