Irregular sleep–wake cycle associated with malignant brain tumor in an adolescent

We report an adolescent case of malignant brain tumor who presented with an irregular sleep–wake cycle as the first significant clinical symptom. The patient was referred to us with a 1-year history of irregular sleep–wake cycle. Subsequently, she was diagnosed with a brain tumor in left temporal lobe, which severely compressed the brain stem. Postoperatively, her sleep–wake cycle normalized, suggesting that the tumor caused reversible dysfunction of the circadian rhythm. Irregular sleep–wake rhythm is most commonly seen in elderly with neurodegenerative disorders. This case suggests that organic causes should be considered when an irregular sleep–wake pattern is seen in adolescents.