Doctors in Italy have successfully transplanted windpipes into two cancer patients in an innovative procedure that uses stem cells to allow a donated trachea to regenerate tissue and create an organ biologically close to the original, they said Friday. The 31-year-old Czech and 19-year-old British patients are in good condition and have been released from the hospital in Florence just weeks after the surgery. The British woman was speaking after only three or four days, said Dr. Walter Giovannini, the director of the AOU Careggi hospital where the surgeries took place on July 3 and 13. "This is a unique solution for a problem that had none, except the death of the patient," Giovannini said. Surgeons have been making advances in the transplant of windpipes, but previous cases have mostly focused on patients whose windpipes have been physically damaged due to trauma.