Maligner Granularzelltumor des Gro�hirnmarkes

Abstract

This is a report of the second known case of a primary malignant granular-cell tumor of the cerebral hemispherical white matter. Two cell types may be distinguished apparently representing different developmental stages of otherwise identical tumor cells. Quantitative histochemical and biochemical studies have shown that tumor cells were containing markedly elevated levels of DNA and RNA. Only few ribosomes and polysomes could be detected, however, by electron microscopy. While cytophotometry disclosed only slightly elevated cytoplasmic proteins, there was a distinct increase in total protein concentration of tumor tissue per unit weight, as measured by conventional techniques. It is suggested that this increase is mainly attributable to structural proteins of cellular and subcellular elements of multiplicating malignant cells. A ratio of RNA to DNA in excess of 1 was found for white matter derived from the central tumor, while the ratios of control tissue were lowered to values far below one due to postmortem changes greatly reducing tissue concentrations of RNA. No detailed characterization of RNA was attempted. The nuclear DNA content of tumor cells reached values equivalent to chromosomal hexadekaploidy. This was in sharp contrast to control data from an Abrikossoff tumor of the oral cavity and from a neurohypophyseal tumorette ("choristoma"), respectively, displaying diploidy only associated with a much lesser increase of cytoplasmic RNA and proteins. Qualitative lipid studies were consistent with a marked active demyelination of the tumor centre as indicated by a severe reduction of cerebrosides and sulfatides and the presence of cholesterol esters. In addition there was a striking loss of phosphatidylethanolamine and a lesser one of sphingomyelin of white matter of both the tumor-stricken and the contralateral unaffected hemispherical regions, possibly suggesting a generally disturbed metabolism of myelin. It is not clear whether these general changes were resulting from the presence of the unilateral tumor or from precocious cerebral involution.

Intracerebral granular cell tumor

“…Many authors hold the view that granular cells may descend from various different kinds of cells. Both reports on the existence of filaments in granular cells [8] and of granular cells in astrocytic gliomas [6] as well as our observations mentioned above [7] and the positive reaction for GFAP in this case are consistent with the hypothesis that astrocytes may be involved in the origin of granular cells. Malignant intracerebral GCT's are extremely rare.…”

“…Silver impregnation showed a similarity of granular tumor cells to pituicytes [4]. Some authors supported the concept that granular cells are mesenchymal cells of the histiocytic type [8]. This case was studied both clinically and by autopsy.…”

“…The second (autoptical) case report concerned a malignant GCT in the white matter of the left cerebral hemisphere [8]. Recently we observed a malignant GCT in the left parietal lobe [7].…”

Morphological and immunohistochemical characterization of granular cells in non‐hypophyseal tumours of the central nervous system

“…The most common intracranial site is the region of the infundibulum [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] . However, GCT can be found in cranial and peripheral nerves 5,[22][23][24][25][26][27][28][29] as well as within cerebral hemispheres [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] (Table 1).…”

Granular cell tumour of the brain and its cellular identity

“…Ule examined the granular cells cytochemically and histochemically, and concluded that the granular cells possibly originated from glial cells 27 We encountered two cases of granular cell tumour of the cerebral hemisphere, and report the results of histochemical study of these tumours.…”