Heterologous transplantation of cerebral and cerebellar astrocytomas

Genomic stability and instability in different neuroepithelial tumors. A role for chromosome structure?

Selected childhood and adult neoplasm exemplify fundamental differences in their propensity for genomic change. DNA replication is essential for the formation of neuroepithelial tumors, probably because the genome can be remodeled. Nonetheless, several differentiated and stable childhood neoplasms retain their nuclear controls for differentiation. In contrast, rapidly arising gliomas often show a variety of phenotypic changes. Genomic plasticity and instability allow gliomas to flexibly adapt to new environments. Gene changes (in DNA) can be limited in childhood tumors whereas more widespread genetic changes in malignant gliomas indicate a fundamental alteration in many chromosome regions. Can such regions be defined? We used one repeated DNA sequence (TTAGGG)n, present at the end of all normal human chromosomes, to investigate chromosome termini in more detail. Pulsed-field gel electrophoresis showed this region can be unusually variable, as several other multilocus probes did not reveal comparable changes. Because telomeres form unique chromosomal structures, and are thought to provide essential signals to position chromosomes in the interphase nucleus, it was pertinent to assess these regions by in situ hybridization. Many telomeric domains localized at variable as well as interior nuclear positions in glioma cells. These positions, which are presumably abnormal, may be generated by the DNA variants observed. Such position changes may contribute to the more general 'disorder' observed in glioma nuclei. Other chromosome domains with a unique DNA-protein structure may define additional genomic loci that are preferentially modified in neoplasia. A fundamental understanding of chromosome structure should clarify the problem of multilocus instability in glioblastoma.

Optic nerve gliomas. II. Cytological characteristics. Observations on cell and tissue cultures

Cytological characteristics of optic nerve gliomas were studied parallel with histological structures in cell and tissue cultures. Histologically the tumours consisted of four different cell types: spindle-shaped elongated cells, round cells, stellate forms, and multinucleated cells. Dynamic properties of cultured optic glioma cells showed that stable cellular elements of the parent tissue arise from two fundamental populations, viz from elongated (piloid), and from round cells. Cells of both populations displayed a series of changes in the course of their cultures. A certain part of the slender elongated cells enlarged and became plump piloid cells of various shapes, or big stellate astrocytes. Giant multinucleated variants of these forms also emerged by fusion of the mononucleate forms. The round cells gradually turned into immature Astrocytes, and by a subsequent cell fusion they gave birth to big stellate cells. With the ageing of the cultures a polymorphous cellular picture developed which was mainly due to the active migratory and intracellular movement of the elongated and round cellular elements. Mitoses played a negligible role in this process. Several characteristics suggest that the round shapes are immature glia cells, and represent the least differentiated elements among all the cell components. The stellate and giant multinucleated forms might be considered as end-products of glia cell differentiation and they could originate both from the elongated and the round cells.

Long-term prognosis in children with benign cerebellar astrocytoma

In 44 children with benign cerebellar astrocytoma, operated on between 1935 and 1959, two histological types could be distinguished, namely, a so-called juvenile type (31 children) and a diffuse type (13 children). All the children were followed to April, 1976, and the histological review was performed without knowledge of the survival in the single patient. For children with the juvenile type of cerebellar astrocytoma the 25-year cumulative survival rate was 94%, as against 38% for children with the diffuse type. It has thus been demonstrated that the morphological difference between the two types corresponds to a marked difference in survival rate.

Tumors of the optic nerve

This is a review of primary and secondary tumors of the optic nerve. The emphasis is an optic nerve gliomas and meningiomas. Optic nerve gliomas are slowly growing astrocytic neoplasms of the anterior visual pathways, the majority of which occur within the first two decades of life, with equal sex incidence in about 1 of 200,000 patients presenting with eye complaints. The incidence is greater in neurofibromatosis. The typical presentation is visual impairment in a verbal pre-school child with optic canal enlargement and optic atrophy. An intraorbital location of the tumor leads to axial, irreducible, non-pulsatile proptosis. An intracranial location may disturb hypothalamic and pituitary function and produce hydrocephalus. Ocular findings may also include limited motility on a mechanical-restrictive basis, a pupillary relative afferent defect, nystagmus, and variable, non-specific visual field defects. Roentgenographic studies may show concentric unilateral enlargement of the optic canal with preservation of a well corticated margin, a fossa under the anterior clinoid process in continuity with the optic canal ('J'-shaped sella), and findings of increased intracranial pressure. On pathologic examination the tumor is a smooth, fusiform, intradural enlargement of the optic nerve. Histologically there is proliferation of elongated (pilocytic) astrocytes in reticulated patterns with intervening microcystic spaces containing mucosubstance and surrounding reactive hyperplasia of the arachnoid. Mitoses are not found. The diagnosis is clinical X-ray studies and brain scan should be performed. The differential diagnosis is that of unilateral proptosis in a child and includes acute ethmoiditis, hyperthyrobidism, craniostenosis, other neoplasms, Hand-Schuller-Christian disease, and orbital hemorrhage due to trauma. Surgical resection is performed in cases with unilateral optic nerve involvement, the surgical approach being determined by tumor location. Bilateral or chiasmal cases are treated with radiotherapy when progression occurs. Malignant optic nerve gliomas and optic nerve hyperplasia are also discussed. Optic nerve meningiomas arise from the nerve sheath and are to be distinguished from orbital meningiomas arising from ectopic arachnoidal cells or those secondarily involving the orbit by extension from adjacent sites. Up to 80% of orbital meningiomas occur in females, in two age peaks, 25% in the first decade, and the rest in the 5th decade. Meningiomas present with visual loss and may produce proptosis, papilledema and/or optic atrophy, retinal striae, opticociliary shunts, limitation of extra-ocular movements, and lid edema, Signs of von Recklinghausen's disease should be sought. X-rays are the mainstay of diagnosis. Orbital meningiomas are composed of cells in sheets or in whorls with some spindle shaped cells. Calcifications are typical. Usually the dura is penetrated and the orbit invaded. Primary orbital meningiomas are locally infiltrating but do not metastasize. Complete local excision en bloc is recommended...

Serial propagation of Creutzfeldt-Jakob disease in guinea pigs

The transmission and serial propagation of Creutzfeldt-Jakob disease from man to guinea pigs are reported. The latency, symptomatology, and morphology of the infection during the first four passages are presented. The incubation period between the first and subsequent passages was halved. One hundred percent take, morbidity, and mortality were achieved in all inoculated animals. All guinea pigs developed a subacute spongiform virus encephalopathy with marked neuronal destruction in the cerebral cortex and subcortical grey structures. The neuronal loss resulted in cerebral atrophy and hydrocephalus ex vacuo.

Chorioallantoic membrane heterotransplantation of human brain tumors

Specimens of human tumors were taken from the operating room and directly heterotransplanted to chick chorioallantoic membranes. Seventy-one percent of the eggs survived the procedure and 41% of the tumors appeared viable after 1 week. Microscopically, the first-generation heterotransplants resembled the parent tumors. Many specimens showed evidence of growth, but in most of them there was also some degree of necrosis. The necrosis increased with serial heterotransplantation, so that tumor propagation usually was not possible beyond the second to third transplant generation; nevertheless, it was found that almost any histological type of intracranial tumor could be grown for short periods of time at least on the chick chorioallantoic membrane.