I didn't have chemo,none for my cancer ,but did have radiation. The radiation/oncologist told me I would have bald patches at the exit sites and it could take weeks and that it would grow back 3 months later. I lost no hair at all.
I had asked about eyelashes and he'd said that eyelashes are strong,implying that nothing would happen to them. Half of them on the top and half on the bottom disappeared from the affected eye. About 8 months later they began to grow back. Another 10 months later they are still shorter than those for my other eye and the top ones look like they have been bleached a little ,instead of being brown.
So now I put mascara on the 2 bottoms and on the one top set of lashes. They still look quite different as my 2 eyes are also different shapes thanks to surgery. Also thanks to surgery I lost half an eyebrow which won't grow back. That too, is a pain as I either pencil one on or powder it on ,neither very easily or well or I just don't bother.