Gadolinium is not necessary for surveillance MR imaging in children with chiasmatic-hypothalamic low-grade glioma.

BACKGROUND: Patients with chiasmatic-hypothalamic low-grade glioma (CHLGG) have frequent MRIs with gadolinium-based contrast agents (GBCA) for disease monitoring. Cumulative gadolinium deposition in the brains of children is a potential concern. The purpose of this study is to evaluate whether MRI with GBCA is necessary for determining radiographic tumor progression in children with CHLGG. METHODS: Children who were treated for progressive CHLGG from 2005 to 2019 at Texas Children's Cancer Center were identified. Pre- and post-contrast MRI sequences were separately reviewed by one neuroradiologist who was blinded to the clinical course. Three dimensional measurements and tumor characteristics were evaluated. Radiographic progression was defined as a 25% increase in size (product of two largest dimensions) compared with baseline or best response after initiation of therapy. RESULTS: A total of 28 patients with progressive CHLGG were identified with a total of 683 MRIs with GBCA reviewed (mean 24 MRIs/patient; range, 11-43 MRIs). Radiographic progression was observed 92 times, 91 (99%) on noncontrast and 90 (98%) on contrast imaging. Sixty-seven progressions necessitating management changes were identified in all (100%) noncontrast sequences and 66 (99%) contrast sequences. Tumor growth > 2 mm in any dimension was identified in 184/187 (98%) noncontrast and 181/187 (97%) with contrast imaging. Metastatic tumors were better visualized on contrast imaging in 4/7 (57%). CONCLUSION: MRI without GBCA effectively identifies patients with progressive disease. When imaging children with CHLGG, eliminating GBCA should be considered unless monitoring patients with metastatic disease.

Profound clinical and radiological response to BRAF inhibition in a 2-month-old diencephalic child with hypothalamic/chiasmatic glioma.

Infants with low-grade glioma (LGG) have a poor survival. BRAFV600E mutation has been identified in pediatric LGG; however, the use of BRAF inhibitors in infants has never been reported. A 2-month-old with V600E mutant hypothalamic/chiasmatic glioma progressed on chemotherapy resulting in profound visual loss, massive ascites, and diencephalic syndrome. Initiation of dabrafenib resulted in rapid and sustained disappearance of clinical symptoms and a profound sustained cytoreduction. BRAF inhibition was safely tolerated with dramatic clinicoradiological response, suggesting early targeted therapy is a viable option in infants with LGG. A re-evaluation of current management paradigms in this population is warranted to leverage the potential benefit of upfront-targeted therapies.

Long-term outcome of centrally located low-grade glioma in children.

BACKGROUND: Optimal management of children with centrally located low-grade glioma (LGG) is unclear. Initial interventions in most children are chemotherapy in younger and radiation therapy (RT) in older children. A better understanding of the inherent risk factors along with the effects of interventions on long-term outcome can lead to reassessment of the current approaches to minimize long-term morbidity. METHODS: To reassess the current treatment strategies of centrally located LGG, we compared the long-term survival and morbidity of different treatment regimens. Medical records of patients primarily treated at Texas Children's Cancer and Hematology Centers between 1987 and 2008 were reviewed. RESULTS: Forty-seven patients with a median follow-up of 79 months were included in the analysis. The 5-year overall survival and progression-free survival (PFS) for all patients were 96% and 53%, respectively. The 5-year PFS for those treated initially with RT (12 patients; median age, 11 years [range, 3-15 years]) and with chemotherapy (28 patients; median age, 2 years [range 0-8 years]) were 76% and 37%, respectively (log-rank test P = .02). Among children who progressed after chemotherapy, the 5-year PFS after salvage RT was 55%. Patients diagnosed at a younger age (<5 years) were more likely to experience endocrine abnormalities (Fisher exact test; P<.00001). CONCLUSIONS: Effective and durable tumor control was obtained with RT as initial treatment. In younger patients, chemotherapy can delay the use of RT; however, frequent progression and long-term morbidity are common. More effective and less toxic therapies are required in these patients, the majority of whom are long-term survivors.

Spontaneous intratumoural and intraventricular haemorrhage associated with a pilomyxoid astrocytoma in the hypothalamic/chiasmatic region.

Pilomyxoid astrocytoma (PMA) is a rare, low-grade glioma that is recognised as a variant of pilocytic astrocytoma. There have been few reports on this pathologic entity presenting with spontaneous haemorrhage. In this study, we report a rare case of PMA in the hypothalamic/chiasmatic region presenting with intratumoural and intraventricular haemorrhage. An external ventricular drain was urgently inserted. A ventriculo-peritoneal shunt (VP) was undergone 4weeks thereafter. The patient received fractionated Gamma Knife radiosurgery in another hospital 3weeks after the VP shunt. Three months later, subtotal resection of the tumour was performed in our hospital via a pterional approach. The pathological diagnosis was PMA. Postoperatively, no adjuvant therapy was given, and the neurologic deficits were improved. However, the presentation of endocrine deficits remained. Notably, PMAs in the hypothalamic/chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage may result in a severe condition and long-term impairment of endocrine function. Long-term follow-up is required to monitor the recurrence of the tumour and endocrinopathy.