Pontine glioblastoma multiforme initially presenting with leptomeningeal gliomatosis

Leptomeningeal metastases in pediatrics: magnetic resonance image manifestations and correlation with cerebral spinal fluid cytology

BACKGROUND

Detection of leptomeningeal metastases is fundamental to a complete evaluation of central nervous system (CNS) or non-CNS tumor with suspected involvement of the neuroaxis. Our purpose was to assess the appearances of different magnetic resonance (MR) sequences in the diagnosis of leptomeningeal metastases and correlate those positive findings with the cerebral spinal fluid (CSF) cytology results.

METHODS

The authors reviewed the medical records and MR image manifestations of leptomeningeal metastases from 18 children who had positive MR findings and retrospectively correlated them with CSF cytologic results. There was a uniform MR protocol and the patients were examined with the same sequences.

RESULTS

The abnormalities included pial-arachnoid disease (n = 16), disease coating the nerves (n = 12), hydrocephalus (n = 3) and subependymal metastases (n = 2). Enhanced T1 images were better than unenhanced fluid attenuated inversion recovery (FLAIR) and T2 to delineate cranial and spinal leptomeningeal metastases. In our sample, seven out of 18 cases were cytologically negative on a single lumbar puncture.

CONCLUSIONS

Contrast-enhanced MR imaging can be invaluable, detecting the false-negative lumbar punctures. FLAIR and diffusion images can be helpful in diagnosing leptomeningeal metastases of non-enhancing primary tumors. Prognosis was more related to the primary tumor type than to the leptomeningeal enhancement MR pattern.

Unusual case of leptomeningeal dissemination of a diffuse pontine high-grade astrocytoma in a child

A 12-year-old girl was seen in our hospital and diagnosed with diffuse pontine glioma. Treatment with radiotherapy was suggested, but the parents rejected this plan and took the child to another hospital where partial resection of the tumor was performed. The histological diagnosis was anaplastic astrocytoma. Returning to our hospital, the parents agreed to radiotherapy which was given in a total dose of 54 Gy. However, 3 months after completion of radiotherapy, the child developed widespread leptomeningeal dissemination of her disease and died 12 months after the initial diagnosis. Since no effective curative methods of treatment exist for patients with diffuse pontine gliomas and surgical intervention is obsolete in this situation and may facilitate leptomeningeal dissemination of the disease, further innovative methods of treatment are needed to improve the bleak prognosis of these patients.

Prognostic significance of intracranial dissemination of glioblastoma multiforme in adults

OBJECT

The clinical outcome and treatment of adult patients with disseminated intracranial glioblastoma multiforme (GBM) is unclear. The objective in the present study was to assess the prognostic significance of disseminated intracranial GBM in adults at presentation and at the time of tumor progression.

METHODS

Clinical data from 1491 patients older than 17 years and harboring a GBM that had been diagnosed between 1988 and 1998 at the University of California at San Francisco neurooncology clinic were retrospectively reviewed. Dissemination of the GBM (126 patients) was determined based on Gd-enhanced magnetic resonance images. Classification of dissemination was as follows: Type I, single lesion with subependymal or subarachnoid spread; Type II, multifocal lesions without subependymal or subarachnoid spread; and Type III, multifocal lesions with subependymal or subarachnoid spread. Subgroups of patients were compared using Kaplan-Meier curves that depicted survival probability. The median postprogression survival (PPS), defined according to neuroimaging demonstrated dissemination, was 37 weeks for Type I (23 patients), 25 weeks for Type II (50 patients), and 10 weeks for Type III spread (19 patients). Patients with dissemination at first tumor progression (52 patients) overall had a shorter PPS than those in a control group with local progression, after adjusting for age, Kamofsky Performance Scale score, and time from tumor diagnosis to its progression (311 patients). When analyzed according to tumor dissemination type, PPS was significantly shorter in patients with Type II (33 patients, p < 0.01) and Type III spread (11 patients, p < 0.01) but not in those with Type I spread (eight patients, p = 0.18).

CONCLUSIONS

Apparently, the presence of intracranial tumor dissemination on initial diagnosis does not in itself preclude aggressive treatment if a patient is otherwise well. A single focus of GBM that later demonstrates Type I dissemination on progression does not have a worse prognosis than a lesion that exhibits only local recurrence.

Atypical external hydrocephalus with visual failure due to occult leptomeningeal dissemination of a pontine glioma

The authors report on the case of a diffuse pontine glioma in a 5-year-old boy in whom radiologically and cytologically occult leptomeningeal metastases led to the development of an atypical "external" hydrocephalus, associated with grossly elevated intracranial pressure (ICP). Initial neuroimaging demonstrated only mild communicating ventricular dilation associated with a noticeable enlargement of the subarachnoid space, particularly over the surface of the frontal lobes; these features are not usually associated with significantly elevated ICP. Possible pathophysiological mechanisms resulting in this unusual clinical presentation are discussed. Early recognition of the severity of the raised ICP despite the paucity of clinical and radiological signs may have averted the development of blindness due to optic atrophy.