In 1891, a New York doctor named William B. Coley injected a mixture of beef broth and Streptococcus bacteria into the arm of a 40-year-old Italian man with an inoperable neck tumor. The patient got terribly sick—developing a fever, chills, and vomiting. But a month later, his cancer had shrunk drastically. Coley would go on to repeat the procedure in more than a thousand patients, with wildly varying degrees of success, before the US Food and Drug Administration shut him down.