Wow, this really isn't very black and white... I suppose it's like having some treatment for cancer that is ugly and grueling. Then discovering an elegant cure

Wow, this really isn't very black and white... I suppose it's like having some treatment for cancer that is ugly and grueling. Then discovering an elegant cure. The cure, however, has some mind-manipulating exploit that is only known to you. What do you do? Cure people from unnecessary suffering of cancer? Or avoid giving people a vulnerability, unknown to everyone else?