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PubMed1984

Concanavalin A target cells in human brain tumours.

Using a lectin-peroxidase method, Concanavalin A binding was examined on formalin-fixed paraffin-embedded biopsy specimens (n = 143) of the most frequent central nervous system tumours. The brain tumours included oligodendrogliomas, astrocytomas, glioblastomas, ependymomas, neurinomas, meningiomas, medulloblastomas and plexus papillomas. In oligodendroglioma cells, only a weak granular intracytoplasmic staining was observed. The astrocytomas showed a strong reaction in fibrillary astrocytes and in tumour areas undergoing small cystic degeneration. Staining of protoplasmic astrocytes was weaker; pilocytic astrocytes demonstrated poor perinuclear staining. Intracytoplasmic Con A binding in gemistocytic astrocytes was distinct but inconstant and rather diffuse. In the glioblastomas the lymphocyte-like small astrocytes were negative. Giant multinucleated astrocytes stained strongly. In ependymomas no or at most a weak perinuclear reaction was observed, whereas the acceptor density was as high as in the normal ependymocytes in areas where the tumour was capable of producing organotypical structures. Plexus papillomas showed a strong intracytoplasmic staining comparable to the normal plexus epithelial cell. This feature was preserved in the malignant variants. In general, meningiomas and neurinomas were negative. Xanthomatous-degenerated meningioma cells, however, showed a distinct to strong intracytoplasmic staining. This feature was characteristic for the xanthomatous subtype of meningiomas. Granular cells with strong intracytoplasmic Con A staining often occurred at the border of fibrillary to reticular differentiated areas of neurinomas. Medulloblastomas were completely negative. Our results indicate that Con A binding to human brain tumours is specific and rather cytotypical than histotypical . The Con A acceptor density is probably related to the grade of differentiation. Lectin mapping of tumours leads to cytotypical binding patterns which may contribute to the differential diagnosis of neoplasias.

Astrocytoma↗
PubMed1988

Ependymomas: a clinicopathologic study.

Since 1924, when ependymomas were first classified as a distinctive glial neoplasm by Bailey, much has been published concerning these tumors, but there are important points of interest that are still not clear. In order to study more fully the clinical and pathologic characteristics of the ependymoma, we identified 62 patients with histologically proven neoplasms. Twenty-two were supratentorial, 21 were infratentorial, and 19 were intramedullary spinal cord tumors. These groups had mean ages of 17, 7, and 41 years, respectively, at the time of first symptoms. The presenting and accompanying symptoms were related to location and included headaches, nausea, visual changes, hemiparesis, and neck, back, and radicular pain. Neurological signs included papilledema, nystagmus, gait disturbance, cranial nerve palsies, altered mental status, paraparesis, and sensory dysfunction. Radiologic modalities of particular importance included computed tomography and myelography. Surgery and radiation therapy were the primary treatment modalities with median survival times from first symptoms being 92, 36, and 117 months for the above groups, respectively. Based on computer-generated survival curves, several characteristics significantly affected survival. These included tumor site, age, and neuraxis metastases. In patients with supratentorial tumors, cranial nerve palsies, microcystic changes, and mitotic figures were important, while in patients with infratentorial tumors, widened sutures, increased head circumference, age, epithelial features, and subependymal features significantly affected survival. Patients who had complete gross resection of a spinal cord tumor had no recurrences or mortality.

Brain Neoplasms↗
PubMed1991

Intracranial metastasis of a choroid plexus papilloma originating in the cerebellopontine angle region: a case report.

The authors present a rare case in which a choroid plexus papilloma originating in the left cerebellopontine angle region metastasized and formed a space-occupying lesion in the right temporal region. A 46-year-old woman with choked disks presented with two separate mass lesions in the right temporal and the left cerebellopontine angle regions. Magnetic resonance imaging exhibited the relationship between the tumors and the surrounding structures. To our knowledge, no case has been reported in which a choroid plexus papilloma originating in the cerebellopontine angle region formed a space-occupying lesion in the right temporal region.

Brain Neoplasms↗
PubMed1994

Studies of childhood brain tumors using immunohistochemistry and microwave technology: methodological considerations.

The immunohistochemical detection of antigens in archival tissue sections has been hampered by the poor reactivity of certain polypeptides in conventional formalin-fixed, paraffin-embedded material. For example, the poor reactivity of neurofilament proteins (NFPs) in surgical and autopsy specimens has been a major drawback of previous large, retrospective, clinicopathologic studies of pediatric primitive neuroectodermal tumors (PNETs), also known as medulloblastomas. We report our experience with a method of antigen retrieval which greatly enhanced the immunohistochemical detection of neuronal and glial intermediate filament proteins, retinal S-antigen (RSA), and the proliferating cell nuclear antigen (PCNA) in archival, paraffin-embedded, formalin or Bouin's-fixed, pediatric brain tumors, particularly PNETs. The technique involves adding a single brief step to an established avidin-biotin complex (ABC) immunohistochemical protocol (Vectastain Elite Kit). This step involves boiling tissue sections in distilled water for 5 min in a microwave oven. The specificity of staining was consistent with known cell and tissue specificities of the well-characterized monoclonal antibodies used and there was minimal background. Synaptophysin (SYN) staining was unaffected by heating and immunoreactivity of the low affinity nerve growth factor (p75NGFR) and the neural cell adhesion molecule (NCAM) were lost. The enhanced detection of neuronal and glial antigens in routinely prepared, formalin-fixed, archival material should facilitate large retrospective clinicopathologic studies designed to assess the prognostic implications of differentiation in PNETs and to better understand the biology of these tumors.

Adult↗
PubMed1984

Expression of muscarinic binding sites in primary human brain tumors.

The expression of muscarinic binding sites was examined in a collection of primary brain tumors of different cellular origins and various degrees of dedifferentiation, as compared to control specimens. Eleven gliogenous tumors were examined, all of which contained substantial amounts of muscarinic binding sites. Most of the other tumor types examined did not display detectable binding of [3H]N-methyl-4-piperidyl benzilate ([3H]4NMPB). Scatchard analysis indicated the existence of homogeneous antagonist sites in both normal forebrain and glioblastoma multiforme, with Kd values of 1.2 nM and 0.9 nM, respectively. The density of muscarinic binding sites varied between tumors from different patients, and also between specimens prelevated from different areas of the same tumor. This variability, as well as the average density of binding sites, appeared to be larger in highly malignant tumors than in less malignant ones. In contrast, the density of muscarinic receptors from control specimens was invariably high, but within the same order of magnitude. To test whether the muscarinic binding activity in the brain tumors is correlated to other cholinoceptive properties, cholinesterase activity was also examined. Individual data for density of [3H]4NMPB binding sites were then plotted against corresponding values of cholinesterase activity. The pattern of distribution of these values was clearly different in tumor specimens, when compared to that observed in samples derived from non-malignant brain. Our observations indicate that human brain cells of gliogenous origin are capable of expressing muscarinic binding sites, and that, if a correlation exists between muscarinic receptors and cholinesterase levels in gliogenous tumors, it differs from that of non-malignant brain tissue.

Adult↗
PubMed1996

Telomeric associations in the progression of chromosome aberrations in pediatric solid tumors.

Telomeric association (tas) is a cytogenetic phenomenon in which chromosome ends fuse to form dicentric, multicentric, and ring chromosomes. We observed clonal tas in six pediatric solid tumors of various types and histological grades studied using short-term in situ culture and G-banding techniques. These tumors included a neurilemoma, an undifferentiated (embryonal) sarcoma of the liver (UESL), two anaplastic astrocytomas (AA), one case of glioblastoma multiforme (GBM), and a neuroblastoma (NB) of the kidney. Cytogenetic data from all six tumors demonstrated multiple numerical and structural aberrations including tas. The tas appeared to be a secondary aberration in these tumors, however, it was possible to follow the progression of the telomeric chromosome aberrations in several cases. In all but one case (UESL) the loss of chromosome segments occurred. Tas of 11p was observed in three of the six tumors, two of which showed the subsequent loss of 11p (AA and AB). In addition, tas of 4p was seen in three tumors, two of which showed clonal tas of 4p with 22q. Tas of 10p, 21p, and 22q were all observed in at least two different tumors. The clonal telomeric fusions of 4p with 22q, recurring tas of 11p, and the subsequent loss of the short arm of 11 demonstrated here, suggests that some chromosome regions are subject to nonrandom instability and sometimes loss.

Adolescent↗
PubMed1983

Intracranial tumors with risk of dissemination in neuroaxis.

The experience of the Radiotherapy Service, Clínica Puerta de Hierro, Madrid (Spain), in the treatment of intracranial tumors with risk of neural axis dissemination is analyzed. In 15 years (1964-1979) 415 primary central nervous system tumors were studied and treated; 67 corresponded to tumors with risk of meningeal dissemination. Clinical dissemination in cerebrospinal fluid was proven in 14 patients. The actuarial survival of 10 years for patients with neural axis dissemination, without prophylactic treatment to the neuroaxis, is 14% with an average survival of 10.5 months. In approximately 20% of meduloblastomas, ependymal and pineal region tumors, meningeal metastases at some distance from the primary tumor can take place. Patients at risk wtih these types of neoplasia must be identified, and an adequate radical therapeutic focus devised, not only for the primary tumor, but also for the risk of dissemination.

Adolescent↗
PubMed1985

A beam alignment device for matching fields.

When radiation treatment is delivered to adjacent or contiguous tumor volumes with multiple fields, the geometric alignment of the beams is particularly critical. A beam alignment device has been developed that enables precise matching of such fields.

Breast Neoplasms↗
PubMed1986

Impact of improved local control on survival.

Estimates of the gain in survival, if all local failures were eliminated, indicate that many more patients could be cured provided the efficacy of treatment of the primary and regional disease were substantially improved. The expected gain in survival is assumed to be the gain in local control, less the loss due to distant metastases and intercurrent disease among the new local control subjects. The observed incidence of DM among local failure patients may be higher than among local control patients; this excess in incidence of DM is assumed to result from metastases established secondary to the persistent or recurring tumor. A powerful argument that higher local control rates would result in more cured patients is the high incidence of long-term survivors after salvage surgery for local failures. Examples of higher survival associated with more effective local therapy are presented from the literature for medulloblastoma, ependymoma, carcinoma of the oral cavity-oropharynx, carcinoma of the urinary bladder, carcinoma of the prostate and carcinoma of the rectum. For Stage I-II cancer of the breast, the reduction of an already low local failure rate by combining surgery and radiation has a very small impact. For tumors, such as, early stage breast cancer, where the possible decrease in local failure is small and the loss due to DM is high, a demonstrable gain in survival is not likely. The potential increase in number of survivors among the U.S. cancer population, if the primary-regional disease were regularly treated successfully, indicates large gains for patients with cancer of the uterine cervix, oral cavity-oropharynx, ovary, colo-rectum, non-oat cell cancer of lung, prostate cancer, and bladder cancer. These provide powerful bases for aggressive investigation of new approaches to improvement of local-regional therapies.

Breast Neoplasms↗
PubMed1984

The dependence of nuclear magnetic resonance (NMR) image contrast on intrinsic and pulse sequence timing parameters.

In Nuclear Magnetic Resonance (NMR) the image pixel value is governed by at least three major intrinsic parameters: the spin density N (H), the spin-lattice relaxation time T1, and the spin-spin relaxation time T2. The extent to which the signal is weighted toward one or several parameters is related to the history of the spin system preceding detection. On the simplifying, though not generally warranted assumption that the spin density does not vary significantly in soft tissues, relative tissue contrast can be predicted quantitatively provided the relaxation times are known. Signal intensities and contrast were computed on the basis of the Bloch equations and experimentally determined relaxation times as a function of pulse timing parameters and the data compared with those in images recorded at 0.5T field strength. Significant deviations from the equal density hypothesis were found for gray and white substance. Notably partial saturation but also spin echo and inversion-recovery images are not in full accordance with predictions made on the basis of relaxation times alone.

Brain↗