Antonio de Lancastre was a physician who studied in several European cities, eventually becoming an expert on tuberculosis. At the Sixth International Congress on Tuberculosis, de Lancastre was appointed to a committee charged with the design of hospitals for patients with the disease. De Lancastre served as the personal physician to King Carlos of Portugal who made him the Duke of Lancastre but he did not use the title. He was also decorated by several foreign governments. De Lancastre was co-opted onto the IOC in June 1906, and resigned in July 1912, but never attended an IOC Session.