One of the most irritating things about breast cancer is the lack of certainty around treatment. I mean, you break your leg, you go to the hospital, they set it, put on a cast, give you a pair of crutches, and off you go. Got a sore throat? If the strep test is positive, you’re sent out the door with a prescription for antibiotics. The only thing you need to decide on is CVS or Rite Aid.

But if you’re diagnosed with breast cancer, the path is never straight. Right out of the starting gate,...