Christopher Lyles was diagnosed with inoperable tracheal cancer. But doctors believe they’ve saved his life, using his own adult stem cells. In November doctors in Sweden used the patient’s own bone marrow stem cells to build a new trachea to replace the cancerous one. After Christopher’s stem cells were grown in a lab for two days, they were placed on synthetic windpipe scaffolding. It was then transplanted into his body after doctors removed the cancerous trachea. Anti-rejection drugs weren’t needed since they were the patient’s own stem cells. This is the second such transplant, and the results of the first one were published in the medical journal The Lancet. This life-saving breakthrough, and hundreds of others, are possible without killing humans for embryonic stem cells.