Malnutrition rather than alcohol abuse is the common element in most cases of WKS. Our report may be the first to identify both the clinical and neuropathologic features of the syndrome in a patient with T-cell lymphoma. The coincidence of these two illnesses underscores a need to consider Wernicke's encephalopathy in debilitated individuals with malignancy or other chronic illnesses, highlights an atypical presentation of acute Wernicke's encephalopathy, and demonstrats the precipitation of that syndrome by glucose feeding. Attention to a patient's nutritional status and the liberal use of thiamine may prompt early recognition of the syndrome or prevent it entirely.