Beyene's tracheal tumor was the size of golf ball and extended to the lowest 5cm of the trachea along with both bronchi, making it difficult for him to breath. Given that the trachea is essential, a surgical removal of the tumor alone would not keep Mr. Beyene alive, therefore it was vital to replace the removed section. The procedure, involving the complete removal of the affected area of the trachea and replacing it with a tailor-made artificial structure took Professor Macchiarini and his team 12 hours.
Karolinska Institutet, in collaboration with University College London, UK, used 3D imaging to scan Beyene in order to prepared the scaffold used in this case. Researchers then constructed a glass model of the affected area of his trachea to be replaced. The glass was then used to shape the synthetic scaffold, prior to being sent to the Karolinska Institutet to have the stem cells inserted. The scaffold was populated using Beyene's own stem cells, turning it into a working airway.
According to Prof. Macchiarini, his method provides advantages over other techniques in transplantation and regenerative medicine because:
- There are no worries regarding rejection as the scaffold is populated using the patient's own cells and no immunosuppressive drugs are required.
- The implant can be tailored to the patient's body size and shape as it is artificially constructed.
- Other transplants require human donors which can involve long waiting periods. This method requires no human donor.
- Constucts can be made-to-fit for individuals (and tracheas) of all sizes, including children.
Prof. Gudbjartsson, explains:
"The patient has been doing great for the last 4 months and has been able to live a normal life. After arriving in Iceland at the start of July, he was 1 month in hospital and another month in the rehabilitation center. Already at the rehabilitation center he could start to work on his Master of Science Thesis in Geophysics, a scientific project that he has been working on for the last years at the University of Iceland here in Reyklavik. For the last two months he has been able to focus on his studies and the plan is the he will defend his thesis at the end of this year."
My Beyene stated: "I am so grateful to everyone that has made this happen."
Several other high-profile transplants have been conducted by Professor Macchiarini in his career. The most famous case being that of Claudia Castillo, the then 30-year old Colombian woman who was the first person to receive tissue-engineered tracheal transplant in 2008. Although, unlike Beyene'a case, Castilo's procedure required a human donor.
A 30-year-old man from Maryland, USA, who also had primary cancer of the airway, is the second patient to receive a bioartificial scaffold transplantation from Prof. Macchiarini. The scaffold used in this case was created from nanofibres and therefore, according to Prof. Macchiarini, represents a further advance from the transplant Beyene received. Prof. Macchiarini's team is now hoping to use the same technique in order to treat a 13-month old South Korean infant.
Professor Macchiarini concludes:
"We will continue to improve the regenerative medicine approaches for transplanting the windpipe and extend it to the lungs, heart, and oesophagus. And investigate whether cell therapy could be applied to irreversible diseases of the major airways and lungs."
In a joint comment, Dr. Harald C Ott and Dr Douglas J Mathisen, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA, explain that the method shows promise and the need for bioartificial grafts is significant.
"To be adjudged successful, bioartificial organs must function over a long time- short-term clinical function is an important achievement, but is only one measure of success. Choice of ideal scaffold material, optimum cell source, well defined tissue culture conditions, and perioperative management pose several questions to be answered before the line to broader clinical application of any bioartificial graft can be crossed safely and confidently."