~20 weeks + cancer

I recently discovered a lump in my breast, and after tests, we found out that it's cancer. The particular program deemed best for me looks to be chemo while pregnant (I could also terminate the pregnancy but I simply cannot). Doctors have informed us, and I have read, that chemo while pregnant is ok as long as one is in her second trimester. Still, this is tremendously terrifying. Has anyone experience or knowledge of this? I would appreciate to know if someone has been through this before.