A retired surgeon suddenly developed violent abdominal pain. After losing 21 pounds, he discovered the unexpected cause that was hiding in plain sight.
The medicine, called Leqembi, slowed decline by 27 percent over 18 months compared with placebo, a study showed. But side effects and cost are fueling controversy.
Research using CRISPR gene editing revealed that scientists from more than a century ago were right: extra chromosomes inside cancer cells help drive tumors.