Sleep in children with cancer.

PURPOSE OF REVIEW: Advances in cancer treatment have improved the 5-year survival rate for childhood cancers to over 78%, resulting in a large population of pediatric cancer survivors. There is increasing recognition that sleep intersects with cancer through the circadian control of the cell cycle and that sleep problems are one of the 'effects' of cancer, its treatments, or both. Recognition of these intersections will facilitate new areas of treatment and the use of proven clinical interventions for sleep problems in cancer survivors.

RECENT FINDINGS: Discoveries in circadian biology have revealed that the biologic clocks, which control sleep/wake rhythms, are present in all cells and exert considerable control over the cell cycle. This has opened new opportunities for improving efficacy, decreasing toxicity, or both of cancer therapy through circadian timing of chemotherapy. Excessive daytime sleepiness has emerged as one of the most common, but often unrecognized, sleep symptoms in cancer survivors.

SUMMARY: Sleep complaints are especially common in survivors of childhood cancer who have sustained an injury to the hypothalamus or brainstem, have evidence of endocrine dysfunction, are obese, or have been treated with cranial radiation. If recognized and treated appropriately, sleep problems can be successfully managed.