Chiu Y.-N.TYNG-GUEY WANGChang C.-W.2020-04-082020-04-0820090929-6646https://www.scopus.com/inward/record.uri?eid=2-s2.0-67651095920&doi=10.1016%2fS0929-6646%2809%2960378-8&partnerID=40&md5=005b2f57715bb811652b61e5f49e7171https://scholars.lib.ntu.edu.tw/handle/123456789/483628We report a 47-year-old male stroke patient with nasopharyngeal cancer (NPC) and protein C deficiency. The patient was diagnosed with NPC and received a complete course of radiotherapy. Infarction stroke occurred 28 months after radiotherapy and magnetic resonance imaging of the brain confirmed the diagnosis. Carotid duplex sonography showed 50-79% stenosis in his left internal carotid artery. Coagulation profiles indicated protein C deficiency. After medical treatment and rehabilitation, the patient regained the ability to walk and he could perform most of his daily activities. Radiotherapy-induced carotid stenosis is an exacerbating feature of stroke in patients with protein C deficiency. We suggest early carotid duplex sonography and survey of the coagulation profile to prevent a stroke in patients with NPC. ? 2009 Formosan Medical Association & Elsevier.[SDGs]SDG3adult; article; blood clotting; cancer patient; carotid artery obstruction; case report; daily life activity; disease exacerbation; echography; human; internal carotid artery; male; nasopharynx carcinoma; nuclear magnetic resonance imaging; protein C deficiency; stroke; stroke patient; walking; Carotid Stenosis; Humans; Male; Middle Aged; Nasopharyngeal Neoplasms; Protein C Deficiency; Stroke; Ultrasonography, Doppler, Duplexjournal article10.1016/S0929-6646(09)60378-8195868342-s2.0-67651095920