The first time I saw my oncologist, weeks after surgery, her face was grim. She thought I was stage 4 — the worst case.
This was because she thought she saw something on my ovary indicating the cancer had spread. It had not; I am 100% sure (and tests confirm) that I do not, at this time, have ovarian or any other kind of cancerous tumor. I've been scanned and probed for tumors virtually from head to toe.
As my oncologist explained it, that's why they are attacking the cancer at the cellular level, "mopping up" with an overall preemptive strike, like fire retardant dropped from an airplane after a wildfire. My body is a forest; embers of cancer cells might be lurking and every effort must be made to wipe them out before they spring back to life. It's a good analogy and a strategy that makes sense to me.