One of the biggest mysteries cancer researchers are trying to solve is why colorectal cancer rates are soaring among young adults.  Now the leading cause of cancer-related deaths among men and women under the age of 50, colorectal cancer has become an alarming outlier among a general decrease in cancer mortality in recent decades. But a paper published last month in Nature Medicine that examined the risk of early-onset cancer has provided a new clue, triggering a lively discourse in the science