Medical Revolution Needed for Mars Mission

On the long road to Mars and back to Earth, there’s no emergency room. And on a crowded spacecraft with a small crew, there’s not much room for a full sick bay. There also is no way to know if an astronaut slated to fly to the Red Planet is actually in the early stages of a deadly or debilitating cancer which could develop during the four or five years NASA figures is necessary to visit Mars, explore, and return safely.