When I was diagnosed with breast cancer almost 5 years ago, I was shocked. I got my annual mammogram, did breast self exams, everything I was supposed to do. There were three masses in my breast, none of which were palpable. My oncology doctor said to me that as long as he was looking at my scans, showing him exactly where the masses were he could sort of feel maybe something there. But without the scan, he would’ve given me an absolutely perfect breast exam with no evidence of cancer. All three masses were the same type of cancer, none of them are palpable. They were fast growing and likely developed between the time of my last mammogram and the one that showed something. People can be stupid and people can be rude. You can use my experience as a breast cancer patient who got regular mammograms and did everything right. None of that stopped the development of cancer. None of it is really her business, but if you have to keep in contact with this woman for whatever reason You might want to use it as a teaching moment. Personally, I would drop her like a hot potato.