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PubMedDate not supplied

Accuracy of cytologic diagnosis of central nervous system neoplasms in sterotactic biopsies.

The cytohistologic correlation is reported for 112 of the 128 consecutive sterotactic aspiration biopsies performed on patients with clinical and neuroradiologic evidence of brain tumors investigated at the Neurosurgery Department, Karolinska Hospital, from 1976 to 1979. The cytodiagnostic accuracy of benign and malignant tumors was 87% when adequate cell material was obtained. In 17 benign tumors of the sellar region, the diagnostic rate was 88%; cytologic examination independent of histologic biopsy is feasible in this area. The cytodiagnostic accuracy for 95 malignant central nervous system (CNS) tumors was 87% after adjusting for the appreciable sampling error inherent in the use of a stereotactic procedure during the early phase of the study. Two histopathologically proven infectious lesions were reported cytologically as benign. The main microscopic problems were the recognition of highly differentiated astroglial neoplasms and the differential diagnosis between poorly differentiated brain neoplasms and metastases to the CNS. Cytodiagnostic accuracy of CNS tumors can be increased by technical improvements in the stereotactic device, diagnostic experience and immunochemical staining.

Biopsy, Needle↗
PubMed2005

Expression of urokinase-type plasminogen activator receptor (uPAR) in primary central nervous system neoplasms.

The cellular receptor for urokinase-type plasminogen activator receptor (uPAR) is a member of the glycosylphosphatidylinositol (GPI) anchored protein family. It is a specific cell surface receptor for its ligand, urokinase-type plasminogen activator, which catalyzes the formation of plasmin from plasminogen to generate the proteolytic cascade and leads to the breakdown of the extracellular matrix. uPAR has been shown to correlate with a propensity to tumor invasion and metastasis in several types of non-central nervous system tumors. In this study, the authors examined the immunohistochemical expression of uPAR in 65 primary brain tumors (5 pilocytic astrocytomas, 5 diffuse astrocytomas, 6 anaplastic astrocytomas, 8 glioblastomas, 5 oligodendrogliomas, 4 oligoastrocytomas, 6 anaplastic oligoastrocytomas, 4 gangliogliomas, 4 ependymomas, 5 medulloblastomas, 6 schwannomas, 5 meningiomas, 2 atypical meningiomas). The specimens were evaluated for intensity of immunostaining (0-3 scale), cellular localization of staining, and specific or unique patterns of staining. Some degree of uPAR expression was observed in all tumors. A significant positive correlation (P = 0.0006) between tumor grade and staining intensity was identified within the astrocytoma/glioblastoma subgroup, suggesting a possible correlation with anaplastic change and propensity to tumor invasion. Expression of uPAR in nonmalignant, noninvasive tumors such as schwannoma and meningioma suggests that uPAR may have other biologic functions in addition to promotion of tumor invasion.

Brain Neoplasms↗
PubMed1978

"Concentration x time" methotrexate via a subcutaneous reservoir: a less toxic regimen for intraventricular chemotherapy of central nervous system neoplasms.

Neurotoxicity associated with intrathecal methotrexate therapy has been shown to correlate with elevated concentrations of the drug in the cerebrospinal fluid as well as with the total cumulative dosage. In our study 19 patients with meningeal leukemia were randomized to receive courses of intraventricular methotrexate via an Ommaya reservoir consisting of either single injections of 12 mg/sq m/dose or a low-dose "concentration x time" (C x T) schedule of 1 mg every 12 hr for 3 days. There were no significant differences between the two treatment groups in the rate of remission induction, the number of relapses, or the durations of remission. The mean (+/- 1 SD) cumulative methotrexate dose was 66 +/- 41 mg/sq m in the C x T group and 173 +/- 64 mg/sq m in the 12 mg/sq m/dose group (p less than 0.005). Neurologic toxicity occurred in one of the eight patients in the C x T group and in seven of ten patients in the 12 mg/sq m/dose group (p less than 0.05). These observations suggest that the C x T dosage schedule is less neurotoxic and equally effective in the treatment of central nervous system leukemia.

Adolescent↗
PubMedDate not supplied

Volumetric analyses of central nervous system neoplasm based on MRI.

Morphometric analyses were performed using an objective semiautomated algorithm on 5 sequential three-dimensional T1-weighted magnetic resonance imaging scans of a metastatic choroid plexus carcinoma, concurrent with a course of chemotherapy. The 5 scans were positionally normalized in a three-dimensional coordinate system for uniform definition of the borders of the mass. Volumes were calculated for the gadolinium-DTPA enhancing and nonenhancing cystic-appearing regions. Volumetric changes of up to 145% were measured using this method which were associated with changes in the calculated (spherical) radii of only up to 2.7 mm. Volumetric changes of up to 59% were not appreciated by visual inspection, most probably due to irregular borders and positional variability across the scans. Volumetric analyses were also performed on the right cerebellar hemisphere, producing a 1.83% coefficient of variability across the 5 scans. The growth rates of this mass were estimated from the sequential computations, permitting in vivo observations on tumor behavior otherwise not obtainable. These analyses demonstrate the potential of this morphometric method to detect significant volumetric changes, and illustrate its use to define in vivo the growth properties of central nervous system tumors in response to therapeutic interventions.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

New technique for removable implantation of radionuclides in central nervous system neoplasm by ultrasonic guidance.

Introduced here is a new technique for the insertion of removable tubes into a brain tumor guided by a real-time ultrasonic B-mode scanner as a preliminary stage for interstitial brachytherapy of malignant brain tumors. Because tube insertion is conducted while watching in real time the tumor echo displayed on the cathode ray tube, the tube-positioning locations for insertion into the tumor can be freely selected with this technique. Additionally, the length of the tube that remains within the tumor bulk can be easily measured and recorded during the operation. Moreover, in that all these procedures can be carried out in the operating room, the operation will be performed under aseptic conditions and in a shorter time. These are the major advantages of this technique.

Brachytherapy↗
PubMed1992

Vertex field verification in the treatment of central nervous system neoplasms.

Increasing sophistication of computerized brain tumor treatment plans has enabled clinicians to devise increasingly complex field combinations to spare as much normal brain tissue as possible. These treatment plans often call for the use of a vertex field. This report describes a simple, useful technique for the verification of the vertex (or any non-coplanar) field on the treatment machine--a procedure that is impossible with conventional port film techniques.

Brain Neoplasms↗
PubMed1995

The incidence of primary central nervous system neoplasms before and after computerized tomography availability.

The observed incidence of primary intracranial neoplasms has increased dramatically among the elderly over the past several years. It is unclear to what extent this increase can be attributed to improved detection by new imaging technology and what portion might represent a true increase in incidence. The first computerized tomography (CT) scanner was operative in Norway in 1975 and became available in all geographical regions within 4 years. The author analyzed incidence data from the population-based Cancer Registry of Norway, placing particular emphasis on the basis for diagnosis (histological, imaging, or clinical findings) for the registrations. In the decade from 1983 to 1992, when the use of CT was widespread, incidence rates of primary intracranial neoplasms for individuals aged 55 to 74 and above 74 years were, respectively, 1.76 (95% confidence interval (CI), 1.63-1.90) and 3.35 (95% CI, 2.70-4.15) times the rates in 1963 to 1972 before CT was available. For persons older than 74 years, the relative incidence increase was 1.98-fold (95% CI, 1.53-2.56) for histologically verified tumors; 15.20 (95% CI, 7.80-29.61) when based on imaging (without histological evidence); and 3.33 (95% CI, 1.93-5.76) when based on clinical diagnosis (without imaging or histological evidence). In this age group, the increase for gliomas was 1.77 (95% CI, 1.18-2.65) and 2.28 (95% CI, 1.53-3.39) for meningioma patients. The present study demonstrates that new imaging technology has improved the diagnostic yield of primary intracranial neoplasms. For those older than 74 years, a large part of the three-fold incidence increase from the pre-CT decade 1963 to 1972 to the post-CT decade 1983 to 1992 can be attributed to improved tumor detection.

Adolescent↗
PubMedDate not supplied

Coexpression of genes involved in apoptosis in central nervous system neoplasms.

PURPOSE: Apoptosis plays a crucial role in normal development and mediates tumor response to chemotherapy. This study investigated the pattern of apoptotic gene expression in brain tumor tissue specimens and cell lines. MATERIALS AND METHODS: BCL2, BCLXL, BCLXS, and BAX transcripts were amplified using reverse transcriptase polymerase chain reaction in 7 high-grade gliomas (HGGs), 7 ependymomas, and 6 cell lines (2 glioblastomas, 3 medulloblastomas, and 1 supratentorial-primitive neuroectodermal tumor [PNET]). Immunohistochemical staining for BCL2, BCLX, BAX, and p53 was performed in 7 pediatric low-grade gliomas (LGGs) and 7 pediatric HGGs. RESULTS: Six of seven gliomas, all ependymomas, and all glioblastoma and medulloblastoma cell lines expressed BCLXL and BAX. BCL2 expression was only detected in the supratentorial PNET line PFSK. BCLXS was absent in all tumors. By immunohistochemistry, no glial tumors stained positively for BCL2. Similar BAX and BCLX protein expression was observed in LGG and HGG. Three of five glioblastomas showed significant p53 expression. CONCLUSIONS: Coexpression of proapoptotic and antiapoptotic genes in human brain tumors supports the hypothesis that the relative expression of competing genes determines apoptotic threshold.

Apoptosis↗
PubMed1998

Cerebrospinal lesions simulating central nervous system neoplasm.

There is a significant number of inflammatory, vascular or demyelinating diseases which may simulate clinically and radiologically primary or metastatic neoplasms of CNS. An incorrect diagnosis of CNS tumor may cause a fall of treatment plans including radiation therapy and chemotherapy. Not infrequently to define a correct diagnosis such cases require surgical procedures. The present report reviews the pathologic features of these space-occupying lesions presenting with signs and symptoms suggestive of brain neoplasms. Surgical pathologists may encounter diagnostic difficulties particularly when dealing with small tissue samples. The knowledge of basic histological features of these non-neoplastic conditions or the application of immunohistochemical and in situ hybridization techniques are essential to their recognition.

Journal Article↗