Abstract
BACKGROUND: Wernicke encephalopathy is a neurological disorder caused by thiamine deficiency, commonly seen in alcoholic populations but also involving other circumstances that may lead to thiamine deficiency. The recognition of Wernicke encephalopathy often depends on clinicians' keen ability to detect its typical triad of features; however, most cases do not present with the full constellation of signs, which complicates the timely identification of Wernicke encephalopathy. CASE SUMMARY: This case report describes a patient with nasopharyngeal carcinoma who developed abnormal ocular function and ataxia following concurrent chemoradiotherapy, without a history of alcohol abuse. With the aid of radiological examinations, he received a timely diagnosis and treatment; however, his symptoms did not fully resolve during follow-up. CONCLUSION: For patients with malignant tumors exhibiting neurological symptoms, clinicians should consider the possibility of Wernicke encephalopathy and provide prophylactic thiamine therapy.