Researchers test ‘holy grail’ tech that could end chemo for some cancer patients

People with colorectal cancer, the fourth most common cancer in the U.S., are often prescribed unnecessary chemotherapy after their cancer is completely gone. The hope is that some patients can be spared after clinical trials of high-technology treatments end and are evaluated in a few years. For decades, doctors have removed people’s colorectal tumors and decided whether their patients needed subsequent chemotherapy by considering several risk factors. This method was imprecise and sometimes people who didn’t need chemotherapy got it anyway. There is now a potentialpath forward. New genetic s...