Clinical Trial of Stem Cell Based Tissue Engineered Laryngeal Implants

This study aims to test a new groundbreaking treatment for narrowing of the voicebox and upper windpipe, which can be due to injury, inflammatory disease or cancer treatment. Narrowing of the voicebox or upper windpipe can leave patients dependant on a tracheostomy tube to breath through (a tube or hole in the neck), which can require a high level of care with regular hospital visits and can lead to recurrent chest infections. Regular surgical procedures may be necessary to widen the airway. Speaking may be very difficult or not even possible, breathing is usually a struggle and swallowing can also be affected. Patients feel very tired all the time. The new treatment tested by this study is an implant that will partially replace the voicebox or upper windpipe in order to cure the narrowing. The implant is based on a human donor voicebox or windpipe that has been processed with detergents and enzymes in order to remove all the cells from the donor, leaving a 'scaffold' of connective tissue. The patient's own stem cells are removed from the bone marrow, then are grown on the scaffold in the laboratory. These cells will form the cartilage in the wall of the scaffold. A split skin graft from the patient may be needed to line the inside of the implant. The implant can be considered 'living' due to the cells grown on it, and this type of treatment is referred to as 'tissue engineering' or 'regenerative medicine'. Once these cells have attached and started to grow on the scaffold, it is ready to be implanted into the patient, and an operation is performed which occurs in two separate stages. The final stage of the operation involves removing the narrow section of voicebox or upper windpipe and implanting the scaffold to reconstruct it. Patients will be followed up for two years after this operation, with investigations such as CT scans, examination of the voicebox and windpipe with a flexible camera (bronchoscopy) and blood tests performed at specific times. It is inten