Putrescine as a biochemical marker of malignant brain tumors.

Putrescine, spermidine, and spermine levels were determined in normal brain and central nervous system-related tumor tissues obtained at operation from 50 patients. The biochemical data were correlated with morphological histopathological descriptions of the same tissues. There was little variation in putrescine levels in normal cerebral cortical tissue. Subcortical white matter had lower putrescine but higher spermidine content than those of the overlying cortex. Putrescine levels were elevated in all astrocytomas assayed, and the magnitude of this elevation was proportional to the malignancy of the tumor as determined by histopathological criteria. In contradistinction, putrescine content of "benign" tumors was generally equal to or lower than that of the normal cerebral cortex. Spermidine and spermine levels varied widely in the tumors assayed and did not correlate with criteria of malignancy. It is concluded that putrescine may be a good biochemical marker of malignancy in central nervous system-related tumors.

Synaptophysin: a sensitive and specific marker for ganglion cells in central nervous system neoplasms.

Synaptophysin, a 38-kilodalton glycoprotein found in synaptic vesicle membranes, has been shown to be a sensitive marker of neuroendocrine differentiation in non-central nervous system (CNS) tumors. We analyzed the patterns of synaptophysin immunoreactivity in CNS neoplasms in comparison with various normal CNS sites in biopsies. Normal gray matter structures all showed a diffuse punctate granular pattern of neuropil staining without staining of neuronal cell bodies. In contrast, neoplastic ganglion cells in 18 of 18 gangliogliomas/gangliocytomas showed intense immunoreactivity outlinging the borders of the cell bodies. Focal staining was also seen in five of 16 primitive neuroectodermal tumors and in one of three central neurocytomas, but these tumors had a finely granular neuropil pattern of immunoreactivity more like that of normal gray matter than like that of the gangliogliomas. All 35 examples of pure gliomas of various types showed no immunoreactivity. Our data highlight synaptophysin as a sensitive and specific marker of both neuronal lineage and neoplastic character in gangliogliomas.

Lipocortin-1 immunoreactivity in central and peripheral nervous system glial tumors.

We examined the cellular distribution of lipocortin-1 (L-1), a major physiologic substrate for the epidermal growth factor receptor/kinase, in 122 central nervous system (CNS) and peripheral nervous system (PNS) neoplasms using the peroxidase-antiperoxidase technique with a polyclonal antibody specific for L-1. Extensive L-1 immunoreactivity was demonstrated in many CNS tumors; in 11 of 21 glioblastoma multiformes, in five of 12 anaplastic astrocytomas, and in five of 14 astrocytomas. Significant numbers of immunoreactive ependymocytes or astrocytes were also seen in six of 13 ependymomas. In contrast, no immunostaining was detected in the oligodendrocytes in any of ten oligodendrogliomas. PNS tumors, found in two of five malignant nerve sheath tumors, 13 of 15 schwannomas, 13 of 17 neurofibromas, and 14 of 15 traumatic neuromas, also contained considerable L-1 immunoreactivity in Schwann cells or mast cells. These findings raise the possibility that L-1 may participate in the proliferation or subsequent differentiation of neoplastic astrocytes, ependymocytes, and Schwann cells.

In vitro magnetic resonance properties of CNS neoplasms and associated cysts.

Fresh surgical specimens of central nervous system (CNS) neoplasms were analyzed with particular attention to differences between the T1 and T2 values of the solid and cystic components. Delineation of solid tumor from cyst is important, particularly when surgical intervention is planned, since only the solid portion need be excised. Total protein concentration determinations and microimmunoelectrophoresis for protein distribution and characterization also were performed on the fluid specimens. To diagnose a lesion on magnetic resonance based on T1 and T2 measurements, one must first have a catalog of values on which to base that diagnosis. The authors are reporting such values at 0.25 T. In addition, protein analysis of the fluid specimens has shown that the cysts of the CNS associated with CNS neoplasms are, in fact, transudates rather than collections of cerebrospinal fluid (CSF). Their T1 should permit differentiation from solid portions of neoplasms and from non-neoplastic syringohydromyelia.

So-called extraskeletal Ewing's sarcoma. Report of a case with ultrastructural analysis.

The light and the electron microscopic features of an extraskeletal round-cell tumor resembling Ewing's sarcoma are described. Ultrastructural observation revealed features similar to Ewing's sarcoma of bone. Variable agrees of nuclear complexity are described. These soft tissue tumors are probably composed of undifferentiated mesenchymal cells; there is no ultrastructural evidence to indicate the cell of origin.

Cellular blue nevus ("melanocytoma") of the spinal meninges: electron microscopic and immunohistochemical features.

A primary cellular blue nevus (melanocytoma) of the spinal canal in a 21-year-old woman is reported. Light microscopic examination revealed a melanotic neoplasm with histological patterns resembling schwannoma, dermal nevi, and neuroblastic-like tumor. The ultrastructural features of the neoplastic cells were similar to those in dermal blue nevi and melanomas. There was no evidence of arachnoidal cell differentiation. Immunohistochemistry revealed positive reactions for S-100 protein and neuron-specific enolase in many cells and no reactions for glial fibrillary acidic protein, cytokeratins, epithelial membrane antigen, 70-kD neurofilament protein, or Leu-7. Vimentin was strongly positive in the melanocytic cells as well as in the arachnoidal cells of involved meninges. The ultrastructural and immunohistochemical features support the nevoid nature of this tumor, which is frequently mislabeled as "melanotic meningioma."

Hormones and tumours in central nervous system (CNS): steroid receptors in primary spinal cord tumours.

On the basis of the studies reported on steroid receptors in brain tumours, cytoplasmic and nuclear estrogen (ER) and progesterone (PR) receptors have been examined in forty primary spinal cord tumours: fifteen neurinomas, three neurofibromas, nine meningiomas, nine ependymomas, two astrocytomas, one oligodendroglioma and one hemangiopericytoma with the exchange method in the presence of sodium thiocyanate for ER and using the synthetic progestin R5020 for PR. Regardless the type of the tumour, ER have been detected with a higher incidence in male than in female patients (78% versus 59%). PR had the same incidence in male and in female patients. The neurinoma was the oncotype more constantly provided with steroid receptors: nuclear ER, in fact, has been found with an incidence of 75% in male and of 43% in female patients. This oncotype is usually provided in both sexes with PR. Ependymomas is spinal tumour with the highest incidence of cytosol ER both in male and in female patients. On the basis of the above results reported it can be assumed that hormonal factors might be involved in the occurrence as well as in the growth of spinal cord tumours. Therefore it can be hypothesized that hormonal treatment might favourably be used as an adjuvant therapy in some selected patients with receptor positive spinal tumours.

Estrogen and progestin receptors in acoustic and spinal neurilemmomas. Clinicopathologic correlations.

Estradiol and progestin receptors were studied in 20 patients with neuraxial Schwann cell tumors, and their presence was correlated to the clinicopathologic features and the amount of preoperative corticosteroid therapy. Based on an arbitrary cutoff value of 200 fmol per gram of tumor as indicative of a positive receptor value in breast cancer, 4 and 13 of the neurilemmoma tissue samples could be considered as positive for estrogen and progesterone receptors, respectively. Whereas there was no convincing correlation between the estrogen and progestin receptor activity and the age, sex, or menopausal status of the patients, overweight patients had significantly higher estrogen and progestin binding values. The correlation between the amount of preoperative prednisone therapy and the amount of [3H]estradiol and [3H]promegestone binding revealed no dose relationship. Correlating [3H]estradiol and [3H]promegestone content with the histologic type of the schwannomas (Antoni types A and B, respectively), we were not able to draw conclusions, because of the predominance of Antoni type A over Antoni type B tissues in our material. The necessity of nuclear receptor assays, ligand specificity testing, and in vitro studies is stressed as a prerequisite for answering the questions whether neurilemmomas contain genuine sexual steroid hormone receptors and whether these receptors are regulated via an estrogen-estrogen-receptor system as is the case in classical sexual steroid hormone target tissues.

Primary melanotic schwannoma of the spinal canal.

A rare case of primitive melanotic schwannoma of the spinal canal associated with an angiomatous formation pushing against the spinal cord is reported. A study by immunohistochemistry and electron microscopy was performed. The positivity for S-100 protein, demonstrated by immunoperoxidase, could indicate that the tumor originates from the Schwann cell. The ultrastructural findings suggest that Schwann cells are capable of producing melanin. In our case the patient is alive and without evidence of the tumor 3 years after surgery. The existence of benign variants of melanotic tumors arising in the central nervous system is emphasized, based on this case and on those previously reported in the literature.

[Histochemical study of the ground substance in chordoma]. / Etude histochimique de la substance fondamentale du chordome

Using a series of histochemical reactions, the authors studied the intercellular substance of a chordoma and of one of its recurrences, and were able to demonstrate the presence of neutral substance, of acid mucosubstances with carboxyl groups and sulphated groups. The presence in the intercellular matrix of the chordoma of sialic acid was shown, as well as the probable presence of hyaluronic acid.

Epithelial membrane antigen expression in ependymomas.

Twenty-seven ependymomas were studied (18 'benign' or low grade and nine 'malignant' or high grade) by means of a monoclonal antibody to epithelial membrane antigen (E29) and an antiserum to glial fibrillary acidic protein (GFAP). The E29 antibody reacted with 'benign' ependymomas but not with 'malignant' ones. Staining was located on the cell surface and especially that facing rosette lumina. Cells forming papillary structures and ependymal epithelium showed a similar distribution of staining. Glial fibrillary acidic protein (GFAP) reactivity was seen in all tumours, with a perivascular accentuation in 'malignant' ones. Staining occurred in the cytoplasm of scattered cells and in those forming papillary structures, ependymal epithelium and rosettes. Our results may have implications in relation to the cytogenesis of these tumours and may also be useful in the histological assessment of 'benign' versus 'malignant' ependymomas.

A novel intradural extramedullary spinal cord tumor in young dogs.

We have studied an unusual, spontaneous, intradural extramedullary spinal cord tumor in 12 dogs. Animals presented with paraparesis and ataxia early in life (11/12 ranged from 6 to 38 months of age) suggesting that these tumors may be congenital. Various breeds of dogs were represented with four cases in German Shepherds and three in retrievers; there was no sex predisposition. Post-mortem examinations revealed a single intradural mass consistently located between T10 and L2, which produced extensive compression of the spinal cord. Metastasis was never observed and significant pathological changes in other organs were lacking. Microscopic examination revealed solid sheets of ovoid to fusiform cells interspersed with areas of acinar and tubular differentiation. Some areas were rarified and focal squamous metaplasia was observed. Ultrastructural features included the presence of a continuous basal lamina, junctional complexes, microvilli and occasional cilia at the apices of acinar complexes. Immunocytochemical studies did not support a neurectodermal origin. At least 13 case reports of this entity have been previously published and have been designated ependymomas, medulloepitheliomas and neuroepitheliomas. A recent case was diagnosed as a nephroblastoma and we feel that this is an interesting and provocative diagnosis. These tumors could result from remnants of renal primordium which becomes trapped between the dura and the developing spinal cord. However, firm evidence of such a histogenesis is not yet at hand.

Intraspinal pigmented schwannoma with malignant progression.

A case with recurrent pigmented intraspinal tumour with malignant progression is presented. The primary tumour grew around the nerve roots T9 and T10, was attached to dura and infiltrated the vertebral bone tissue. On light microscopy it was comprised of monomorphic cells with large amount of cytoplasmic pigment and many large pigmented globoid bodies. Mitoses were not observed. On electron microscopy, in addition to cytoplasmic melanosomes of regular size, macromelanosomes were numerous. The tumour cells were surrounded partially by basement membrane like material. On these bases a histological diagnosis of benign pigmented tumour of neural crest origin was suggested (a possible pigmented meningioma or pigmented schwannoma). The patient got a recurrence one year after the primary operation. Biopsy from the re-operation showed histologically the same type of tumour with more pleomorphic cells. Subsequently, the tumour grew progressively and metastases were observed in the lungs and in the skin. The patient died two years after the primary operation. The malignant progression of the tumour and other reports on similar tumours was most consistent with a diagnosis of malignant pigmented schwannoma and this was confirmed later on with immunohistochemical staining showing positive staining for basement membrane components, collagen type IV and laminin as well as a positive staining for S-100 protein. The present findings show that despite benign histological features these tumours can behave very aggressively and stress the need of more information on this type of tumour.

Glial fibrillary acidic protein in stromal cells of some capillary hemangioblastomas: significance and possible implications of an immunoperoxidase study.

Thirty-nine hemangioblastomas from 26 patients were studied by the immunoperoxidase method for GFA protein. Reactive gliosis in the form of trapped GFA protein-positive astrocytes or astrocytic cell processes penetrated the margins of all the neuraxial tumors and none of those occurring on nerve roots or in the tumor explants maintained in an organ culture system. Gliosis was especially prominent in tumors recurring after surgical excision or in patients with a long history of tumor. In six tumors, representing both the reticular and the cellular variants of hemangioblastoma, GFA protein-positive stromal cells were also found, chiefly in the periphery of the neoplasma: all these tumors were surrounded by dense reactive gliosis. Four hypotheses accounting for the presence of GFA protein-positive stromal cells are considered: (1) The tumors are astrocytomas. (2) The GFA protein-positive cells are not neoplastic but lipidized or altered reactive astrocytes. (3) The tumors are mixed and partly composed of neoplastic astrocytes. (4) The stromal cells are capable of taking up extracellular GFA protein derived from the adjacent reactive astrocytes. The last of these hypotheses is the most consistent with the collective evidence derived from the histological findings. It implies that the presence of GFA protein in the cytoplasm of a cell does not necessarily establish that the cell is glial. The possibility of uptake of GFA protein by non-glial cells must be considered if dense gliosis is present in the vicinity.

Steroid receptors in CNS: estradiol(ER) and progesterone(PR) receptors in human spinal cord tumors.

To investigate the role of steroid hormones in the occurrence and growth of human spinal cord tumors and to study the biochemical basis of the sex related difference in the incidence of the various spinal oncotypes, ER and PR have been measured in 24 human spinal cord tumors (12 neurinomas, 6 meningiomas, 5 ependymomas and 1 astrocytoma) by means of sodium thiocyanate exchange assay at low temperature and with dextran-coated charcoal method and R5020 for PR. Cytoplasmic and nuclear receptors have been evaluated. Neurinomas are the oncotypes which contained both ER (usually in the nuclear fraction) adn PR: estradiol binding has been found only in one meningioma; ependymomas contained cytoplasmic ER and the astrocytoma had nuclear ER and cytoplasmic PR. The dissociation constant is in favour of a high affinity binding (Kd = 0.15 X 10(-9)M for ERc; Kd = 3.85 X 10(-9)M for ERn; Kd = 8.07 X 10(-9)M for PRc). The overall incidence of steroid receptors in the spinal oncotypes studied is higher in male than in female patients (63.64 vs 46.15% for ER and 100 vs 71.43% for PR). Further studies on a greater number of patients will help to define the correlation between different spinal oncotypes and steroid receptors as well as the possibility of an endocrine therapy as adjuvant treatment for selected patients.

Canine malignant melanotic schwannomas: a light and electron microscopic study of two cases.

Malignant, melanotic schwannoma of the spinal cord was diagnosed in two two-year-old dogs. The neoplastic spindle cells were arranged in a herringbone or storiform pattern; the intracytoplasmic melanin varied in amount in different areas of the two neoplasms. Ultrastructural features including cytoplasmic lamellar premelanosomes and melanosomes, rudimentary cell junctions, scattered pinocytotic vesicles, and remnants of external lamina supported the diagnosis of melanotic schwannoma.

Neuropeptides in gliomas: identification of somatostatin 14 in a medulloblastoma.

Forty nine gliomas were analysed for the following neuropeptides: somatostatin (SS), substance P (SP), neurotensin (NT) and vasoactive intestinal polypeptide (VIP) and the pituitary peptide, adrenocorticotrophin (ACTH). A significant amount of authentic SS was found in a medulloblastoma, and low concentrations of SP and NT immunoreactivity in an ependymoma and cerebellar astrocytoma respectively. The majority of the other gliomas did not contain detectable levels of these five neuropeptides. Low levels of neuropeptides were found in some specimens probably due to contamination with cerebral cortex.

The immunocytochemical localization of GFA protein in experimental murine CNS tumors.

Immunocytochemical localization of GFA protein in formalin-fixed, paraffin-embedded tissue sections by the peroxidase-antiperoxidase method of Sternberger was used to study experimental murine CNS tumors. Transplacental tumor induction in rats by ethylnitrosourea produced oligodendrogliomas and mixed gliomas in the cerebrum and spinal cord, and malignant Schwannomas of the trigeminal nerve. A methylcholanthrene-induced mouse "ependymoblastoma" inoculated intracerebrally in normal and in toxoplasma-infected mice was also studied. A positive reaction of GFA protein antibody was seen in the astrocytic portion of the mixed gliomas; the oligodendrogliomas, the malignant Schwannomas and the mouse "ependymoblastoma" were negative. Staining for GFA protein delineated the astrocytic reaction of neural tissue adjacent to the tumors. The reaction was markedly intensified in the brains of mice infected with toxoplasma. Additionally, ependymal cells near the tumors stained positively for GFA protein; normal ependyma at a distance from tumor remained negative. The technique, which combines a high degree of specificity with great sensitivity and is readily adaptable to routinely processed tissue, should prove a valuable tool in experimental oncology of the central nervous system.

Immunohistochemical demonstration of keratin in canine neuroepithelioma.

Morphological features and immunoreactivity for cytokeratin (CK), glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE) of three canine neuroepitheliomas and three canine ependymomas were investigated. Neuroepitheliomas were in three German shepherds as intradural-extramedullary solitary masses, with spinal cord displacement between T10 and L2. Histologically, they contained tubules and acini, lined by epithelial cells with focal squamous metaplasia, rosette-like structures, and polygonal to spindle-shaped cells between tubules. Acini were empty or filled with a homogeneous, eosinophilic periodic acid-Schiff (PAS)-positive material. Mitotic indices varied from low to moderate. Ependymomas occurred in the third (two cases) and fourth ventricle in adult boxers. Histologically, they were composed of cells with an ill-defined, scant amphophilic cytoplasm, with a central round euchromatic nucleus; cells formed pseudorosettes, with a central fibro-vascular stroma. Neuroepitheliomas stained for CK, but ependymomas did not. Both failed to stain for GFAP, NSE, or phosphotungstic acid hematoxylin (PTAH). Thus, antibodies to cytokeratin are useful to distinguish neuroepitheliomas from ependymomas.

Morphology of early stages of ENU-induced brain tumors in rats.

Tumors were induced in experimental animals in order to investigate early tumor growth with conventional histology and gliofibrillary acid protein (GFAP) demonstration with the peroxidase-antiperoxidase (PAP) method. In one experiment, the animals were killed after transplacental ENU administration, when microtumors were suspected; in the second experiment, the animals were followed up to their natural death and microtumors found at random were used for analysis. Conventional histology revealed 3 types of microtumors: growth restricted to the subventricular matrix, growth in the neighbourhood of the ventricles with obvious or probable connection to the ventricular zones and small tumors observed exclusively in the white matter. The latter tumors by conventional staining were composed of small round cells, considered to be oligodendrocytes. They did not contain GFA-protein positive cells within the tumor. The tumor in presumable and visible connection with the ventricular lining did contain GFAP-positive astrocytes. In the very small subventricular tumors, the small round cells (oligodendrocytes) were in continuous contact with the identical interfascicular glial cells, while GFAP positive astrocytes seemed to stem from the subventricular astrocytes (tanycytes, ependymoglia). The ependyma itself was always preserved. A twofold origin of these experimental tumors with probable development into one common cytological glial type is assumed.