Catching a Cancer

Viral culprits may explain a host of tumors with as-yet unknown triggers

Mentors at the Rockefeller Institute had warned Peyton Rous not to waste his career fooling with “the cancer question.” Then he got the bright idea that tumors might be contagious. Rous extracted part of a sarcoma from a hen, strained out the cells and injected the remnants into another bird.