A 74-year-old man was admitted with lung cancer, and preoperative blood test showed abnormal activated partial thromboplastin time (APTT). Coagulation factor screening and APTT mixing test achieved a diagnosis of acquired hemophilia A (AHA). Bypassing agent therapy was indicated and lobectomy was successfully performed without bleeding complications. APTT returned to normal after the operation without any additional treatment for AHA. The pathogenesis of AHA is still unknown and there is no evidence for hemostatic strategy for AHA patients requiring surgery. This study supports the importance of hemostatic therapy and suggests that malignancy might cause AHA.
Keywords: acquired hemophilia; lung cancer; surgery.