A case of acute myeloid leukemia requiring endotracheal intubation due to airway stenosis caused by laryngeal edema early after pre-transplant conditioning regimen

Mucosal damages that appear early after hematopoietic stem cell transplantation (HSCT) are a frequently observed adverse event. However, there are cases of laryngeal edema due to mucosal damage, narrowing of the airway, and even dyspnea.<br> A 61-year-old man who had a history of receiving 70 Gy of radiation and chemotherapy for hypopharyngeal cancer developed therapy-related leukemia 30 months from his last radiation therapy. The patient's leukemia showed resistant to various chemotherapy treatments, and complete remission was not achieved. Although he had frequent infections during those treatments, the laryngeal edema persisted, but did not progress to airway stenosis. He was in high risk for HSCT since he was not in remission. His Hematopoietic Cell Transplantation-specific Comorbidity Index was scored at 3, and he had received gastrostomy care. However, cord blood transplantation (CBT) was conducted with reduced intensity conditioning regimen 7 months after the onset of his leukemia because of his strong request.<br> Laryngeal edema advanced from mucosal damages early after CBT. The administration of hydrocortisone was not effective, and endotracheal intubation was required because of airway stenosis and dyspnea. In this case, the mucosal damage caused by the conditioning regimen might have triggered severe laryngeal edema at the site of previous irradiation, causing delayed airway constriction and dyspnea. The possibility of severe tracheal stenosis due to mucosal damage and laryngeal edema should be kept in mind when performing HSCT with patients who have a history of radiotherapy to the pharynx.