Chemotherapeutic treatment of extensive optic pathway tumors in infants

Prognostic Factors and Results of Radiation Therapy in Optic Pathway Tumors

Aims and Background

The role of radiotherapy in the management of patients with optic pathway tumors remains controversial. This study analyzes the outcome of patients treated with radiotherapy and attempts to identify the groups of patients that may require early therapy.

Methods

We retrospectively reviewed 36 patients with optic pathway tumors treated with radiotherapy alone (26 patients) or with postoperative radiotherapy (10 patients). Seven patients had optic nerve tumors and 29 patients had chiasmal tumors. The actuarial progression free survival and observed survival probabilities were calculated using the Kaplan-Meier method and differences between curves were evaluated by the Mantel-Cox test. The obtained significant variables in the univariate analysis were analyzed using the Cox proportional hazards model.

Results

The 10-year actuarial progression-free survival (10-y PFS) rate was 86% for patients with optic nerve gliomas and 47% for patients with chiasmal tumors. The 10-year actuarial observed survival (10-y OS) rate was 75% for patients with optic nerve gliomas and 53% for patients with chiasmal gliomas. In the group of patients with chiasmal tumors, progression-free survival and observed survival rates were significantly lower in infants (10-y PFS: 30%; 10-y OS: 37%), in patients with neurological deficits (10-y PFS and 10-y OS: 23%), in patients with signs of elevated intracranial pressure (10-y PFS and 10-y OS: 9%), with hydrocephalus (10-y PFS and 10-y OS: 0%), or with impairment of consciousness (10-y PFS and 10-y OS: 17%). Evaluation by computed tomography scanning was associated with a significantly higher probability of PFS. Radiation doses lower than 50 Gy were associated with significantly lower PFS and OS rates. In the Cox multivariate analysis, presence of neurological deficits and radiation dose significantly influenced observed survival. Presence of hydrocephalus significantly influenced progression-free survival.

Conclusions

The prognosis of patients with chiasmal gliomas presenting with neurologic deficits is poor and should be treated at diagnosis. A minimum tumor dose of 50 Gy is recommended.

Suprasellar pilocytic astrocytoma: one national centre's experience

INTRODUCTION

Pilocytic astrocytomas in the supratentorial compartment make up 20 % of all brain tumours in children with only 5 % of these arising in the suprasellar region. Optic pathway gliomas or suprasellar gliomas are often seen in neurofibromatosis type 1 (NF1) patients. Given their location, suprasellar pilocytic astrocytomas are challenging to manage surgically with high morbidity rates from surgical resection. We assess our cohort of patients with suprasellar pilocytic astrocytoma and document our experience.

METHOD

A retrospective review of patients diagnosed with suprasellar glioma between 2000-October 2012. We included patients diagnosed with optic pathway glioma based on radiological features (with or without biopsy) and those who had a biopsy confirming pilocytic astrocytoma.

RESULTS

Fifty-three patients included (sporadic tumours 24 and NF1 related 29). Fifteen sporadic and four NF1 patients were biopsied. Twelve sporadic and 13 NF1 patients were initially treated with chemotherapy while only 1 patient had radiotherapy initially. Progression was noted in 58 % of the sporadic group and 24 % of the NF1 group. The only significant factor for progression was NF1 status (p = 0.026).

CONCLUSION

Management should be guided by individual patient circumstance. In our cohort, chemotherapy did not significantly improve progression free survival; however, NF1 status significantly correlated with the decreased progression.

Optic glioma warranting treatment in children

PURPOSE

To describe cases of optic pathway glioma (OPG) warranting treatment in children.

METHODS

This is a retrospective review of pediatric patients treated for OPG. The clinical data and imaging studies were obtained from the medical records and radiology files of patients seen at the Pediatric Neuro-Ophthalmology Clinic at the University of Illinois, Chicago and the private office of the author (LMK).

RESULTS

A total of seven cases with an age range of 3-48 months at presentation were reviewed. Three of the patients were also ultimately diagnosed with neurofibromatosis type 1. Presenting symptoms included proptosis, decreased vision, gaze deficit, and nystagmus. Four patients underwent biopsies that confirmed OPG. Six of the patients were treated with intravenous chemotherapy, with three patients requiring a second chemotherapy cycle. One patient was successfully treated with an en-bloc optic nerve excision. Two patients underwent unilateral enucleation owing to globe complications.

CONCLUSION

Although benign tumours, OPG can behave very aggressively in young children. Both chemotherapy and en-bloc excision can be employed for treatment.

Cisplatin/vincristine chemotherapy for hypothalamic/visual pathway astrocytomas in young children

Hypothalamic/visual pathway astrocytomas in children are usually quiescent, but certain cases contain aggressive neoplasms that cause progressive neurological and visual deterioration. Radiotherapy is not recommended in young children because of its adverse effects later in life. This report describes the efficacy of a chemotherapeutic regimen. Four young children with hypothalamic/visual pathway astrocytoma, with a mean of 18 months of age at diagnosis, were treated with chemotherapy. Three patients had diencephalic syndrome at the disease's onset. Three patients with pilocytic astrocytoma were histologically verified, and another infant was clinically diagnosed. A combination chemotherapy using cisplatin and vincristine was administered in a total of 8 cycles in 3 children and 4 in one child. One patient who demonstrated renal insufficiency after 4 cycles of this regimen was treated with additional 4 cycles using carboplatin instead of cisplatin. The acute and subacute hematologic and otologic toxicities were mild, and a transient renal insufficiency in a child during chemotherapy improved. After chemotherapy, tumor regression was documented in 3 patients, and the disease was observed to be stable in one patient with an evidence of intratumoral necrosis on MRI. Three patients showed neurological and endocrinological improvements. These results suggest that this regimen is feasible in young children and may be useful as a first-line treatment for hypothalamic/visual pathway astrocytomas, which in turn may allow potentially deleterious irradiation on the maturing brain to be deferred until the disease progresses.

Optic chiasm glioma, electrolyte abnormalities, nonobstructive hydrocephalus and ascites

A 4-year-old girl with optic chiasm glioma (OCG), nonobstructive hydrocephalus and ventriculoperitoneal shunt is described, in whom marked ascites developed. The ascitic fluid was protein-rich and its amount correlated with cerebrospinal fluid (CSF) protein. The CSF protein level and the amount of ascitic fluid were influenced by chemotherapy. Very unusual hypernatremia, up to 190 mEq/l with no associated alteration in mental status, was also found. It is suggested that altered absorption ability owing to the high protein content was the cause of both the nonobstructive hydrocephalus and the ascites. The unusual well being with very high sodium concentrations may have resulted from osmoreceptor dysfunction, presumably caused by hypothalamic involvement as well as by the high CSF protein. This combination of findings may point toward specific characteristics of OCG. In an effort to reduce the amount of the ascitic fluid, a further chemotherapeutic trial may be done, before converting the shunt to the vetriculoatrial system.

Optic pathway glioma infiltrating into somatostatinergic pathways in a young boy with gigantism. Case report

The authors report gigantism in a 16-month-old boy with an extensive optic pathway glioma infiltrating into somatostatinergic pathways, as revealed by magnetic resonance imaging and immunocytochemical studies. Stereotactic biopsies of areas showing hyperintense signal abnormalities on T2-weighted images in and adjacent to the involved visual pathways provided rarely obtained histological correlation of such areas. The patient received chemotherapy, which resulted in reduction of size and signal intensity of the tumor and stabilization of vision and growth velocity.

Surgery of giant gliomas of chiasma and IIIrd ventricle

During a period of 17 years (from 1976 till now) 45 patients with giant gliomas of the chiasma and the IIIrd ventricle out of a total amount of 120 patients with hypothalamic gliomas were operated. The following classification of tumours was used: I) tumours with predominant anterior growth; II) tumours which infiltrate chiasma and penetrate into the IIIrd ventricle; III) gliomas of the floor of the IIIrd ventricle and the chiasma, growing into the ventricle cavity; IV) tumours of the chiasma, optic tract and thalamus. The authors come to the conclusion, that surgical removal of giant tumours of the chiasma and the IIIrd ventricle, though risk, may result in an improvement or stabilisation of visual functions (77%) and a long period free from recurrencies (9.5%). The postoperative period is relatively favourable and the mortality is low (6%). The main contraindication in our opinion is a wide infiltration of adjacent brain structures by the tumour and spreading along both optical tracts. We consider the giant size of a tumour in itself a sufficient indication for surgery.