mately 70% of patients with TAO develop critical limbthreatening ischemia (CLTI) of Fontaine Class III or higher during progression, and approximately 10% of these patients undergo major amputation surgery. 2 Further, approximately 20% of patients require minor ampu-T hromboangiitis obliterans (TAO; Buerger's disease) is more common among men in their 30s and 40s, and shows a strong causal association with smoking. However, the pathogenesis of TAO remains unknown, and it is categorized as an incurable disease. 1 Approxi-