A fascinating, rapidly emerging concept in the medical field is use of a capsule that is swallowed and captures images that are remotely reviewed. In current versions, the pill-sized plastic capsules take photos at random intervals, a technique that isn't considered adequate for cancer screening.
Newer systems are elaborate and much higher-tech. Two recently caught my attention.
An Israeli company called Cap-Check uses an imaging capsule that contains a tiny device that transmits X-rays, with minimal radiation, to the intestinal wall and back. The analysis of distances creates three-dimensional images of the colon's internal surface. That allows the detection of polyps within the same range of accuracy as standard colonoscopy. Bowel cleansing is unnecessary, since X-ray technology, unlike optics, can "see through" colon content. The information is transmitted to a device like a wristwatch.