[Cerebral infarction related to intracranial radiation arteritis twenty-four years after encephalic radiation therapy]

Primary angiitis of the central nervous system and reversible cerebral vasoconstriction syndrome

Primary angiitis of the central nervous system (PACNS) is one of the most devastating pathologic processes that affect the central nervous system (CNS). It results in exclusive inflammation and destruction of CNS blood vessels. Progressive debilitating unexplained neurological deficit associated with abnormal cerebrospinal fluid (CSF) analysis findings is the typical picture of the disease. CNS biopsy is the gold standard diagnostic test. Immunosuppressive therapy is the core treatment. Reversible cerebral vasoconstriction syndrome (RCVS) is a main mimic of PACNS. RCVS is characterized clinically by recurrent thunderclap headache with or without neurological deficit and normal CSF analysis findings and angiographically by reversible diffuse segmental vasospasm of intracranial vessels. A stepwise diagnostic approach should be followed to differentiate PACNS from RCVS and exclude the other clinical, radiographic, and angiographic mimics.

Late-onset post-irradiation vasculopathy of the posterior cerebral vasculature

Radiotherapy is extensively used in the treatment of malignant tumors of the central nervous system, but may also cause considerable morbidity and mortality, probably through damage to the remarkably vulnerable vascular system. We present two cases of infarction in the posterior cerebral vasculature related to earlier irradiation for a pineal gland tumor. Two patients were irradiated for a pineal gland tumor in young adulthood. Respectively 20 and 35 years later, they presented with a progressive neurological decline, related to early progressive atherosclerosis in the posterior cerebral vasculature. In conclusion, irradiation of the posterior cerebral territory may produce precocious atherosclerosis of posterior circulation vasculature, even decades later. When a progressive clinical decline with accumulating ischemic events is observed, together with signs of atherosclerosis, radiotherapy-related vasculopathy may be considered.

Late effects of conformal radiation therapy for pediatric patients with low-grade glioma: prospective evaluation of cognitive, endocrine, and hearing deficits

PURPOSE

We conducted a prospective trial to evaluate late effects in pediatric patients with low-grade glioma (LGG) treated with conformal radiation therapy (CRT).

PATIENTS AND METHODS

Between August 1997 and August 2006, 78 pediatric patients with LGG (mean age, 9.7 years; standard deviation, +/-4.4 years) received 54 Gy of CRT with a 10-mm clinical target volume margin. Tumor locations were diencephalon (n = 58), cerebral hemisphere (n = 3), and cerebellum (n = 17). Baseline and serial evaluations were performed to identify deficits in cognition, endocrine function, and hearing. Deficits were correlated with clinical factors and radiation dose within specific normal tissue volumes.

RESULTS

Cognitive effects of CRT through 5 years after CRT correlated with patient age, neurofibromatosis type 1 status, tumor location and volume, extent of resection, and radiation dose. The effect of age exceeded that of radiation dose; patients younger than 5 years experienced the greatest decline in cognition. Before CRT, growth hormone (GH) secretion abnormality was diagnosed in 24% of tested patients, and 12% had precocious puberty. The 10-year cumulative incidence of GH replacement was 48.9%; of thyroid hormone replacement, 64.0%; of glucocorticoid replacement, 19.2%; and of gonadotropin-releasing hormone analog therapy, 34.2%. The mean +/- standard errors of the cumulative incidence of hearing loss at 10 years did not exceed 5.7% +/- 3.3% at any frequency.

CONCLUSION

To our knowledge, this is the largest series of prospectively followed children with LGG to undergo irradiation. Adverse effects are limited and predictable for most patients; however, this study provides additional evidence that CRT should be delayed for young patients and identifies the potential benefits of reducing radiation dose to normal brain.