.... Chemotherapy targets rapidly dividing cells (e.g. cancer, hair, blood). Most cells in your body don't undergo mitosis often enough to be affected by chemo.
Besides, we have a host of other treatments for cancer:
...to name a few categories.
So, no this is not even "basically" how we treat cancer.
Maybe you're right. Maybe it's Markov chains all the way down.
The only way I can think to test this would be to "poison" the training data with faulty arithmetic to see if it is just recalling precedent or actually implementing an algorithm.