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R A Morantz

Publications and source records attributed to R A Morantz.

At least 37 records · Page 2Linked to original sources
PubMed1989

Cerebellar astrocytomas in elderly patients with very long preoperative histories: report of three cases.

Three patients, ages 69, 67, and 74 years, respectively, underwent surgical removal of cystic cerebellar astrocytomas. All three had past histories pointing to the existence of a cerebellar lesion for many decades prior to surgery: Patient 1 had had nystagmus on lateral gaze on the side of the tumor since early childhood; Patient 2 had had sensorineural hearing loss on the side of her neoplasm for 38 years preceding the operation; and Patient 3 was diagnosed as having a brain tumor 51 years before the operation. (He has been blind because of pressure hydrocephalus for half a century, but otherwise managed to live a productive farming and family life until he sustained a head injury in a car accident, which forced him to undergo removal of his cerebellar tumor.) The neoplasms in all three instances were found by histological examination to be low-grade astrocytomas. These cases indicate that low-grade cerebellar astrocytomas, which are well known for their characteristically long postoperative courses, may at times manifest a slow growth potential with an exceptionally long preoperative course.

Aged↗
PubMed1988

Potentiation of rat brain tumor therapy by fluosol and carbogen.

We have been using the 9L rat brain tumor model to investigate the effect of the combination of a perfluorochemical emulsion, Fluosol-DA 20%, and carbogen breathing on the therapy of brain tumors. The combination of Fluosol, carbogen breathing, and carmustine (BCNU) was more effective at prolonging survival than was BCNU alone. This difference was small but significant (P less than 0.25). neither Fluosol without carbogen nor carbogen without Fluosol significantly altered the effect of BCNU. Fluosol and carbogen alone did not affect the survival of tumor-burdened rats. Fluosol and carbogen breathing did not alter the effect of single doses of radiation on these tumors. This result supports the hypothesis that 9L brain tumors contain few, if any, critical hypoxic cells. However, these tumors may contain cells which are oxygen deficient but not radiobiologically hypoxic. The Fluosol-carbogen combination may be changing the intratumor environment in such a way that the metabolism or activity of BCNU is altered.

Animals↗
PubMed1988

Effect of spirogermanium and radiation therapy on the 9L rat brain tumor model.

Spirogermanium (SPG) was investigated in the 9L rat brain tumor model in vivo and in vitro. Used at a single ip dose of 50 or 60 mg/kg or at 5 daily doses of 10 mg/kg, SPG was ineffective in prolonging survival of rats burdened with the intracerebrally implanted tumor, i.e., the median survival time (MST) was the same as that for the controls. Only a schedule of 3 X 20 mg SPG/kg every other day improved the MST compared with controls. Single-dose (20-Gy) radiation therapy (RT, cesium-137 whole-head irradiation) did prolong survival. However, when single-dose SPG was combined with RT (1 hr or 1 day before, or 1 hr after RT), the survival response was worse than after RT alone. When the daily SPG was combined with daily RT (5 doses of 6 Gy), survival was no better than after daily RT alone. In vitro, SPG produces a concentration-dependent, exponential decrease in cell survival as measured by colony formation assay. When combined with radiation, there is an additive effect on cell lethality. Aside from the possibility that SPG does not penetrate the rat brain tumor itself, we have no explanation why SPG shows some activity against human brain tumors and is cytotoxic against 9L cells in vitro, yet is both ineffective by itself and fails to potentiate RT in the 9L rat brain tumor model.

Animals↗
PubMed1987

Radiation therapy in the treatment of cerebral astrocytoma.

With the advent of more sensitive diagnostic techniques, we are encountering an increasing number of young patients harboring cerebral astrocytoma. The great danger in such patients is that the astrocytoma cells will undergo dedifferentiation to a higher state of malignancy. An essential question is whether the use of postoperative adjuvant radiation therapy can decrease the incidence of this event. Because a prospective, randomized study has never been carried out, it is extremely difficult to ascertain whether radiation therapy should be given to these patients. This article reviews the main retrospective clinical studies in an attempt to determine whether the addition of radiation therapy increases the length or quality of survival in patients with astrocytoma. Based on this literature review, the following tentative conclusions have been reached: All reported studies are inconclusive; therefore, dogmatic statements as to whether radiation therapy should be used are not warranted. One should try to obtain pathological confirmation of the precise nature of all tumor-like cerebral lesions that have been detected on neuroradiological studies. Consistent with sound neurosurgical judgment, every attempt should be made to carry out a gross total removal of the hemispheric astrocytoma. In the case of such a gross total surgical removal and even in its absence in the case of a juvenile pilocytic astrocytoma, radiation therapy may be withheld and the patient carefully followed for tumor recurrence. In those cases where total removal cannot be accomplished, postoperative radiation therapy seems warranted. Such radiation therapy should be given in a conventional fractionated schedule to a maximum of 5500 rads.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Cerebellar medulloblastoma in a 73-year-old woman.

A case of a 73-year-old woman with cerebellar medulloblastoma is described. The patient presented with the classical symptoms and signs of a medulloblastoma, and radiological findings were also consistent with this entity. Nevertheless, because of the patient's advanced age, the possibilities of metastatic tumor involving the cerebellum or a primary cerebellar lymphoma were considered before operation. Pathological examination of the operative specimen showed a classical medulloblastoma with occasional areas of early neuroblastic differentiation. Immunoperoxidase strains for neurofilaments were of help in confirming the neurogenic origin of the neoplastic cells. Although medulloblastomas in adults are not rare, onset after the age of 50 is exceptional, with only two cases on record in patients 65 or older. The present patient seems to be the oldest individual with a cerebellar medulloblastoma thus far reported.

Aged↗
PubMed1985

Epidemiological findings in a brain-tumor cluster in western Missouri.

A cluster of seven primary brain neoplasms was identified in a town of 3000 population during the 10-year period from 1973 to 1982. With six deaths, this represents an age-adjusted mortality rate 4.1 times greater than expected. No other neoplasms were found to be in excess of the anticipated incidence in this town. When brain-tumor mortality rates in 36 other towns of approximately the same population were calculated, only one other town was found to have an excessive rate. All seven tumors in this study were histologically verified: six were diagnosed as glioblastoma multiforme. Interviews were conducted with patients or next-of-kin to obtain the exposure histories of the patients. A number of respondents reported occupational or residential exposure either to a shoe factory or to one of the several chicken hatcheries in the town. Many of the patients ate fish from local ponds that had previously been used as coal mining strip pits. Two patients were siblings. None of the patients had a history of significant head trauma. This unique situation may provide an opportunity to learn more about environmental risk factors for brain neoplasia. Further epidemiological studies are planned.

Adult↗
PubMed1983

Bleomycin and brain tumors. A review.

A logical inference from the recent reports indicating that malignant brain tumors are composed of a heterogeneous cell population is that combination chemotherapy will be required for effective brain tumor control. For several years we have been investigating the use of Bleomycin as an agent to be used in conjunction with radiation therapy and a nitrosourea compound. Since systemically administered Bleomycin does not cross the blood-brain-barrier and has significant toxicity when used parenterally in high doses, we have studied the use of smaller doses of Bleomycin injected directly into the brain tumor cavity. Such an intracerebral dose was more effective in prolonging survival of rats burdened with experimental 9L gliosarcomas than an intravenous dose that is 25 times as great. The combination of intracerebrally administered Bleomycin and radiation therapy was more effective than either modality alone. Furthermore, the combination of Bleomycin delivered intracerebrally and BCNU given systemically was more effective than either agent used alone. Finally, in a Phase I clinical of Bleomycin given via an Ommaya reservoir to eight patients with recurrent malignant brain tumors, we have demonstrated that individual doses of up to 7.5 units and cumulative doses of up to 255 units can be administered without significant toxicity.

Adult↗
PubMed1983

Depressed T lymphocyte function in brain tumor patients: monocytes as suppressor cells.

Depressed cellular immune function has been demonstrated in patients with a variety of lymphoreticular and nonlymphoreticular neoplasms, including patients harboring brain tumors. In the present study, peripheral T lymphocytes from more than fifty percent of patients with central nervous system tumors, both primary and metastatic, exhibited depressed incorporation of 3H-thymidine in response to phytohemagglutinin (PHA) when tests were performed in the absence of autologous serum. Increased numbers of monocytes were present within mononuclear cell suspensions from brain tumor patients, and most of the cell populations containing elevated monocytes also exhibited depressed responses to PHA. A role for monocytes as suppressor cells was suggested by the finding that partial reconstitution of T cell function could frequently be effected by adherent cell depletion. However, total reversal of the defect was rare and there was no relationship between monocytes and T cell dysfunction in some patients. The results suggest that while monocytes may be involved in the immune depression seen in some patients with a brain tumor, the complete explanation is as yet unknown.

Astrocytoma↗
PubMed1982

In vitro reversal of depressed T-lymphocyte function in the peripheral blood of brain tumor patients.

Peripheral blood mononuclear cells from some brain tumor patients exhibited depressed T-lymphocyte responses to the polyclonal mitogen phytohemagglutinin (PHA). These responses, initially depressed, were restored to near normal by a 24-hour preculture in growth medium. The effect of preculture was mimicked by mild trypsinization before addition of PHA. In addition, cells treated with deaggregated antihuman IgG resulted in greatly reduced responses to mitogen by mononuclear cells from all brain tumor patients. Anti-IgG had no effect if cells were precultured for 24 hours. The results suggest that, in brain tumor patients, depressed immune function associated with tumor progression was caused by suppressor cells which were activated by humoral factors that express IgG antigenic determinants.

Brain Neoplasms↗
PubMed1980

Craniopharyngioma simulating bilateral internal ophthalmoplegia.

A 15-year-old girl had rapid onset of an apparent bilateral internal ophthalmoplegia. Subsequent evaluation revealed a large craniopharyngioma. It is uncommon for a mass to cause such eye findings and unique for a craniopharyngioma to manifest in this fashion.

Accommodation, Ocular↗
PubMed1980

Immunoglobulin bound in vivo to Fc receptor-positive cells in human central nervous system tumors.

Fifteen human central nervous system tumors of various histopathologic types were assessed qualitatively and quantitatively by indirect immunofluorescence for the presence of in vivo bound IgG, IgA, and IgM. The tumors were selected to reflect varying degrees of infiltration with Fc receptor-positive macrophages. The major purpose of the study was to determine the relative contribution of immunoglobulin (Ig) bound to tumor cells as compared to Ig bound to the Fc receptor-positive host macrophages. Of the 15 tumors, 1 tumor contained no detectable IgG, IgA, or IgM, 2 tumors contained only IgG and IgA bound in a smooth, homogeneous pattern to the surface of tumor cells, and 8 contained only IgG, IgA, and IgM attached to Fc receptor-positive cells. Four tumors contained significant numbers of tumor cells with cytoplasmic Ig, and two of those tumors also were infiltrated with Fc receptor-positive cells with membrane-associated Ig. Ig was removed from Fc receptor-positive cells but not from tumor cells by prolonged washing of sections of tumor at 37 degrees C, which suggested that Ig was associated with Fc receptors. That possibility was strengthened by the observation that the IgG subclass distribution of the Fc receptor-associated Ig was predominantly IgG1 and IgG3, whereas no predominant subclass existed for IgG bound to tumor cells. Furthermore, the Fc receptor-associated Ig appeared to be in the form of antigen-antibody complexes because it had a granular quality and because IgA and sometimes even IgM were involved in the Fc receptor-bound complexes.

Antibodies, Neoplasm↗