Cancer survivor too. just wrote about it https://medium.com/@allengparsons/what-to-say-to-a-cancer-patient-340dc31fec78
I used to see the women come in for their turn at radiation. Most had scarves to hide their missing hair. Radiation is no joke if you need to be there. I didn't ask 'what you in for" but I could see the real sadness in the woman's eyes. I respected their privacy but felt I should have said something.