Ophthalmic artery occlusion secondary to radiation-induced vasculopathy

Neurological Complications of Childhood Cancer

Though the treatment of pediatric cancers has come a long way, acute and chronic effects of cancer are still affecting the life of many children. These effects may be caused not only by the malignancy itself but also by the interventions used for the purpose of treatment. This article focuses primarily on the indirect effects of pediatric cancers and their treatment on the central and peripheral nervous system. Chemotherapy, radiation, and stem cell transplantation cause an immune-compromised state and place the patient at risk of infection, the leading cause of mortality in pediatric cancer. The underlying cancer and the treatments also cause neurovascular changes that may lead to neurological sequelae immediately or many years in the future. Chemotherapy and radiation have both immediate and long-term neurotoxic effects on the central and peripheral nervous system. Cancers may also trigger an immune response that damages nervous system components, leading to altered mental status, seizures, abnormal movements, and even psychosis. Knowledge of these effects can help the practitioner be more vigilant for the signs and symptoms of potential neurological complications during the management of pediatric cancers.

ISCHEMIC RETINOPATHY IN NEUROFIBROMATOSIS TYPE 1

PURPOSE

To describe a patient with severe ischemic retinopathy and maculopathy in the context of neurofibromatosis Type 1.

METHODS

Case report illustrated with multimodal clinical imaging. A 16-year-old female with neurofibromatosis Type 1 presented with visual deterioration over several weeks. Her right eye was amblyopic because of an optic nerve glioma treated in childhood with chemotherapy.

RESULTS

Corrected visual acuities were counting fingers in the right eye and 20/150 in the left eye. Examination revealed bilateral optic disk pallor. In the left eye, severe and extensive ischemic retinopathy and maculopathy were noted with collateral formation and neovascularization. Proximal arterial occlusion at the level of the internal carotid and ophthalmic arteries was excluded on neuroimaging, including computed tomography angiography.

CONCLUSION

Neurofibromatosis Type 1 may present in the ocular fundus with a variety of lesion types, including vasoproliferative tumors, hamartoma, uveal melanoma, and hemangioma. Vascular occlusions are relatively uncommon. Ocular ischemic syndrome secondary to moyamoya syndrome is well described in neurofibromatosis Type 1 but was excluded in our patient. A spectrum of retinal microvascular abnormalities has also been described, but disease-specific evidence to guide treatment is lacking.

Infarction following chiasmatic low grade glioma resection

INTRODUCTION

The current SIOP (International Society for Paediatric Oncology)-LGG (low grade glioma) study protocol allows chiasmatic tumours identified as LGG on the basis of neuroradiological characteristics to be treated without histological verification. As some tumours do not respond well to treatment, the search for molecular tissue markers will gain importance for future studies. Anecdotal observations of infarctions after surgery for chiasmatic tumours during central reviewing initiated this study.

MATERIALS AND METHODS

In 84 patients, histology was obtained during 102 interventions in the years 1992-2009 by 33 biopsies, 67 partial/subtotal and 2 total resections. Median age at the time of operation was 5 years (mean 5 years 11 months). We could identify 17 infarctions following partial resection of chiasmatic LGG. Biopsies were not complicated by infarction. Children developing infarction were considerably younger (median 3 years; mean 4 years 5 months) than the patients without infarction (median 5 years 4 months; mean 6 years 2 months). A total of 51 patients with cerebellar LGG (median 7 years; mean 7 years 4 months) served as a control group, with 65 surgical procedures (2 biopsies, 22 partial/subtotal resections and 41 total resections) performed in the years 2004-2009. Only one total resection (1.5%) in this group was followed by infarction.

CONCLUSION

Partial/subtotal resections of chiasmatic LGG in our study population bear a considerable risk for infarction especially in young children. As there is currently no evidence for a better outcome after tumour resection, we suggest that the sampling of tumour tissue should be performed via biopsies whenever possible.

Phase II trial of conformal radiation therapy for pediatric low-grade glioma

PURPOSE

The use of radiotherapy in pediatric low-grade glioma (LGG) is controversial, especially for young patients. We conducted a phase II trial of conformal radiation therapy (CRT) to estimate disease control by using a 10-mm clinical target volume (CTV) margin.

MATERIALS AND METHODS

Between August 1997 and August 2006, 78 pediatric patients with LGG and a median age of 8.9 years (range, 2.2 to 19.8 years) received 54 Gy CRT by using a 10-mm CTV and by targeting with systematic magnetic resonance imaging (MRI) registration. Tumor locations were diencephalon (n = 58), cerebral hemisphere (n = 3), and cerebellum (n = 17). Sixty-seven patients had documented or presumed WHO grade 1 tumors, 25 patients had prior chemotherapy, and 13 patients had neurofibromatosis type 1.

RESULTS

During a median follow-up of 89 months, 13 patients experienced disease progression. One patient experienced marginal treatment failure, eight experienced local failures, and four experienced metastatic failure. The mean and standard error 5- and 10-year event-free (87.4% +/- 4.4% and 74.3% +/- 15.4%, respectively) and overall (98.5% +/- 1.6% and 95.9% +/- 5.8%, respectively) survival rates were determined. The mean and standard error cumulative incidences of local failure at 5 and 10 years were 8.7% +/- 3.5% and 16.4% +/- 5.4%, respectively. The mean and standard error cumulative incidence of vasculopathy was 4.79% +/- 2.73% at 6 years, and it was higher for those younger than 5 years of age (P = .0105) at the time of CRT.

CONCLUSION

This large, prospective series of irradiated children with LGG demonstrates that CRT with a 10-mm CTV does not compromise disease control. The results suggest that CRT should be delayed in young patients to reduce the risk of vasculopathy.