Radiation-induced brain injury after a conventional dose of intensity-modulated radiotherapy for nasopharyngeal carcinoma: a case report and literature review*

Abstract

Abstract A 61-year-old female nasopharyngeal carcinoma patient was admitted to the hospital with sudden cognitive dysfunction one month after Volumetric Intensity Modulated Arc Therapy (VMAT) conventional dose radiotherapy, and the initial diagnosis was radiation-induced brain injury (RBI). After comprehensive treatment with steroid hormones, the patient's condition rapidly improved. Typically, in nasopharyngeal carcinoma patients treated with VMAT, the incidence of RBI is extremely low when the temporal lobe dose is less than 65 Gy or 1% of the volume is less than 65 Gy. When this limit is exceeded, RBI may occur in varying degrees. However, in this case, even though the temporal lobe dose was under the prescribed limit, the patient still experienced RBI. The rare observations in this case can be used as a reference, and clinicians should seriously consider the possibility of RBI in similar cases.