Until My Diagnosis, I Had Never Met Anyone With Colon Cancer

My colon, like yours, is a muscular five-foot-long tube arranged in the abdomen in the shape of a box. Also called the large intestine, it looks like a fleshy, segmented snake surrounding a bunch of twisty worms; the worms are the tubes of the small intestine. The small intestine absorbs nutrients from food, while its large sibling removes water from what’s left via waves of involuntary contractions, which push the increasingly solid mass toward the rectum.

More fascinating, and possibly less gross, the colon is the seat of the much-ballyhooed microbiome, teeming with some 39 trillion bacteria believed to play a major role in the immune system. And the whole gastrointestinal tract, starting with the mouth and ending with the anus, has more neurons than anywhere in the body outside the bra