Differentiation among glioblastoma multiforme, solitary metastatic tumor, and lymphoma using whole-tumor histogram analysis of the normalized cerebral blood volume in enhancing and perienhancing lesions.

BACKGROUND AND PURPOSE: The histogram method has been shown to demonstrate heterogeneous morphologic features of tumor vascularity. This study aimed to determine whether whole-tumor histogram analysis of the normalized CBV for contrast-enhancing lesions and perienhancing lesions can differentiate among GBMs, SMTs, and lymphomas. MATERIALS AND METHODS: Fifty-nine patients with histopathologically confirmed GBMs (n = 28), SMTs (n = 22), or lymphomas (n = 12) underwent conventional MR imaging and dynamic susceptibility contrast-enhanced imaging before surgery. Histogram distribution of the normalized CBV was obtained from whole-tumor voxels in contrast-enhancing lesions and perienhancing lesions. The HW, PHP, and MV were determined from histograms. One-way ANOVA was used initially to test the overall equality of mean values for each type of tumor. Subsequently, posttest multiple comparisons were performed. RESULTS: For whole-tumor histogram analyses for contrast-enhancing lesions, only PHP could differentiate among GBMs (4.79 ± 1.31), SMTs (3.32 ± 1.10), and lymphomas (2.08 ± 0.54). The parameters HW and MV were not significantly different between GBMs and SMTs, whereas the 2 histogram parameters were significantly higher in GBMs and SMTs compared with lymphomas. For the analyses of perienhancing lesions, only MV could differentiate among GBMs (1.90 ± 0.26), SMTs (0.80 ± 0.21), and lymphomas (1.27 ± 0.34). HW and PHP were not significantly different between SMTs and lymphomas. CONCLUSIONS: Using a whole-tumor histogram analysis of normalized CBV for contrast-enhancing lesions and perienhancing lesions facilitates differentiation of GBMs, SMTs and lymphomas.

Diagnostic accuracy and interobserver variability of pulsed arterial spin labeling for glioma grading.

BACKGROUND: Although pulsed arterial spin labeling (PASL) enables the reliable qualitative grading of brain tumors, its use in quantification for glioma grading may be hampered by the limited interobserver variability associated with low spatial resolution. PURPOSE: To assess the interobserver variability and diagnostic accuracy of the relative tumor perfusion signal intensity (rTPS) calculated using PASL in glioma grading. MATERIAL AND METHODS: Fifty-eight patients with 61 cerebral astrocytomas underwent conventional MR imaging and PASL. Receiver operating characteristic analyses were used to determine the optimum thresholds for tumor grading. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for identifying high-grade gliomas were also calculated. Cohen's kappa statistic was used to determine the levels of interobserver variability in the quantitative analysis of PASL. RESULTS: The sensitivity, specificity, PPV, and NPV for determining a high-grade glioma with conventional MR imaging were 77.1, 73.1, 79.4, and 70.4%, respectively. A threshold value of 1.28 for rTPS provided a sensitivity, specificity, PPV, and NPV of 82.9, 96.2, 96.7, and 80.6%, respectively. There was a statistically significant difference in the rTPS between low- and high-grade astrocytomas (1.14 vs. 1.47, P<0.05). In the interobserver variability analysis, substantial agreement was obtained for the quantitative rTPS measurement from PASL (kappa =0.72). CONCLUSION: Quantitative perfusion measurement with PASL can improve the diagnostic accuracy of preoperative glioma grading, as compared to the application of conventional imaging alone. However, the interobserver variability for quantification is substantial.

An endoscopically proven ventriculitis-type, cyst-like intraventricular primary lymphoma of the central nervous system.

Primary ventriculitis form of primary CNS lymphoma (PCNSL) is very rare and difficult to diagnose from radiological findings. A 55-year-woman presented with a cystic mass in the lateral ventricle without evidence of demonstrable malignant cells in the cerebrospinal fluid (CSF). The endoscopic biopsy showed a ventriculitis-like thin web on the surface of the ventricular wall around the foramen of Monro, resulting in obstruction. Pathological diagnosis was non-Hodgkin's lymphoma, B cell type. This case suggests that PCNSL should be considered as a differential diagnosis for a cystic ventricular lesion even with no malignant cells in the CSF.

Brain transplantation of neural stem cells cotransduced with tyrosine hydroxylase and GTP cyclohydrolase 1 in Parkinsonian rats.

Neural stem cells (NSCs) of the central nervous system (CNS) recently have attracted a great deal of interest not only because of their importance in basic research on neural development, but also in terms of their therapeutic potential in neurological diseases, such as Parkinson's disease (PD). To examine if genetically modified NSCs are a suitable source for the cell and gene therapy of PD, an immortalized mouse NSC line, C17.2, was transduced with tyrosine hydroxylase (TH) gene and with GTP cyclohydrolase 1 (GTPCH1) gene, which are important enzymes in dopamine biosynthesis. The expression of TH in transduced C17.2-THGC cells was confirmed by RT-PCR, Western blot analysis, and immunocytochemistry, and expression of GTPCH1 by RT-PCR. The level of L-DOPA released by C17.2-THGC cells, as determined by HPLC assay, was 3793 pmol/10(6) cells, which is 760-fold higher than that produced by C17.2-TH cells, indicating that GTPCH1 expression is important for L-DOPA production by transduced C17.2 cells. Following the implantation of C17.2-THGcC NSCs into the striata of parkinsonian rats, a marked improvement in amphetamine-induced turning behavior was observed in parkinsonian rats grafted with C17.2-THGC cells but not in the control rats grafted with C17.2 cells. These results indicate that genetically modified NSCs grafted into the brain of the parkinsonian rats are capable of survival, migration, and neuronal differentiation. Collectively, these results suggest that NSCs have great potential as a source of cells for cell therapy and an effective vehicle for therapeutic gene transfer in Parkinson's disease.

Treatment of vertebral artery dissecting aneurysms presenting with progressive myelopathy.

Two patients with vertebral artery dissecting aneurysm are presented in which the posterior inferior cerebellar artery (PICA) arose from the wall of the aneurysm. The patients presented with progressive myelopathy due to mass effect on the medulla. One patient was treated with proximal occlusion of the vertebral artery using Guglielmi detachable coils (GDCs). The other patient underwent complete excision of the aneurysm, with reimplantation of the PICA into the vertebral artery proximal to the dissecting aneurysm. We obtained good results with improvement of myelopathy in both patients, but the patient who underwent bypass surgery suffered longstanding palsy of the lower cranial nerves. This report emphasizes that complete aneurysm clipping or excision for such patients is the gold standard of treatment, but preservation of PICA flow may require technically sophisticated surgical techniques. However, even if the aneurysm is not completely eliminated, the myelopathy can be dramatically improved with conservative endovascular treatment with proximal occlusion. Therefore, the choices for treatment in such lesions varies with the angiographic findings, degrees of mass effect on the brainstem, and the patient's physical condition.

The usefulness of external marking in stenting for m1 segment of middle cerebral artery stenosis. Technical note.

SUMMARY: In intracranial stenting procedures, especially for a focal stenosis on the M1 portion of the middle cerebral artery, the anatomical configuration of the middle cerebral artery is changed with the advance of a rigid stent catheter. Therefore, the location of the stenotic portion where the stent is supposed to be deployed, according to pre-measurements on the roadmapping image, could be changed to some degrees. To prevent this error, we put a 30 gauge needle with cap at the orbital rim on the same preliminary vertical line of the distal end of the stenotic portion where the distal end of the stent is supposed to be deployed and the stent deployment is performed under guidance of the external marking on the fluoroscopic image not under roadmapping image.We report our experience of successful elective stenting of middle cerebral artery stenosis using the aid of external marking.

GT1b ganglioside induces death of dopaminergic neurons in rat mesencephalic cultures.

We examined neurotoxicity of GT1b against dopaminergic neurons in vitro. Cultures of mesencephalic cells deprived of serum underwent the loss of 19% of tyrosine hydroxylase immunopositive (TH-ip) neurons. In cultures deprived of serum, treatment with 10-30 microg/ml GT1b attenuated the number of TH-ip neurons by 26-69%, respectively, compared to non-treated cultures. Intriguingly, cultures deprived of serum were more vulnerable to GT1b-induced neurotoxicity. Application of 60 microg/ml GT1b to cultures grown in serum containing media resulted in the loss of 26% of TH-ip neurons, similar to that (28%) observed in serum-deprived cultures treated with 10 microg/ml GT1b. Moreover, in our cultures, absence of nitric oxide (NO) production after GT1b treatment was obvious. The present results strongly suggest direct neurotoxic actions of GT1b against dopaminergic neurons regardless of NO.

The proliferative activity of neurilemomas.

Twenty-one patients with neurilemomas (15 intracranial and 6 intraspinal) received a 1-hour intravenous infusion of 5-bromodeoxyuridine (BrdU), 200 mg/m2 before tumor removal, to label S-phase tumor cells. Excised tumor specimens were stained by the indirect immunoperoxidase method with anti-BrdU monoclonal antibodies to determine the BrdU labeling index, or percentage of S-phase cells. The BrdU labeling index ranged from 0.1% to 3.1% (mean, 0.9%). The BrdU labeling index was greater than 1.5% in four of the 21 tumors (three trigeminal and one spinal). One acoustic tumor in a patient with neurofibromatosis type 1 had a labeling index of 1.3%, which was the highest among the acoustic tumors. The BrdU labeling indices did not correlate with the patient's age, tumor size, or the duration of signs and symptoms. There was no significant difference between the BrdU labeling indices of Antoni type A and Antoni type B tissue. The low BrdU labeling index of most of the intracranial neurilemomas coincides well with the slow growth of these tumors. As the BrdU labeling index may reflect growth potential of individual tumors, it could be used to guide the follow-up patients with incompletely resected tumor.

Prognostic implications of the bromodeoxyuridine labeling index of human gliomas.

This study includes 182 patients with intracranial gliomas who received bromodeoxyuridine (BUdR), 200 mg/sq m intravenously, at the time of craniotomy but before tumor biopsy. The tumor specimens were stained for BUdR using the immunoperoxidase method; the BUdR labeling index (LI), or S-phase fraction, was calculated as the percentage of BUdR-positive cells. The median BUdR LI's for 127 primary moderately anaplastic astrocytomas, highly anaplastic astrocytomas, and glioblastomas (less than 1%, 2.7%, and 7.3%, respectively; range 0% to 38.1%) were not significantly different from those of 55 similar recurrent tumors (less than 1%, 4.3%, and 7.4%, respectively; range 0% to 30.5%). The mean LI was significantly higher in tumors from patients over 50 years of age than in tumors from younger patients (p less than 0.001). The age-related difference in LI's was found in both groups of patients with astrocytomas but not in those with glioblastomas. Kaplan-Meier survival curves showed a significantly greater probability of survival among patients whose tumors had LI's of less than 1% than among those with LI's greater than 5%; survival probability of patients with tumor LI's of 1% to 5% was intermediate between the two extremes. Thus, the BUdR LI appears to reflect the proliferative potential more accurately than the histopathological diagnosis and should therefore be considered an important factor in determining the prognosis of individual patients with intracranial gliomas and in selecting their treatment.

Variability in the proliferative potential of human gliomas.

One hundred forty-three patients with gliomas of astrocytic origin (61 with glioblastomas multiforme (GM) and 82 with astrocytomas) received an intravenous infusion of bromodeoxyuridine (BUdR), 150-200 mg/m2 at the time of surgery, to label tumor cells undergoing DNA synthesis. BUdR-labeled cells were identified by the indirect immunoperoxidase method using anti-BUdR monoclonal antibodies. The percentage of BUdR-labeled cells, or BUdR labeling index (LI), was calculated by microscopic examination of selected viable areas of the tissue sections. The GMs had a median LI of 7.5%, and three quarters of these tumors had LIs greater than 5%. Highly anaplastic astrocytomas (HAAs) and moderately anaplastic astrocytomas (MoAAs) had median LIs of 2.3% and less than 1%, respectively. Among the HAAs, the LI was 1% to 5% in 56% of tumors, greater than 5% in 26%, and less than 1% in 18%. More than 60% of MoAAs had LIs less than 1%, which agrees with the slow clinical progression of this type of tumor, and the remainder had LIs of 1.4% to 9.3%. These results show that histopathologically similar tumors may have different proliferative potentials. Measuring the proliferative potential of individual gliomas is therefore crucial for predicting the prognosis more accurately and for devising more tumor-specific treatment regimens for individual patients.

Correlation of histopathological features and proliferative potential of gliomas.

One hundred fifty-two intracranial gliomas of various types were reviewed in order to correlate the histopathological features with the proliferative potential of each tumor as reflected by the bromodeoxyuridine (BUdR) labeling index (LI). Patients undergoing surgical removal of gliomas were given a 30-minute intravenous infusion of BUdR (150 to 200 mg/sq m) to label S-phase tumor cells. The tumor specimens were stained immunohistochemically for BUdR and processed for routine histopathological diagnosis. The BUdR LI was calculated as the percentage of labeled cells among cells analyzed. Twenty-seven histological features in three categories (degenerative, vascular, and cellular changes) were considered. A significantly higher BUdR LI (p less than 0.05) was found in tumors with necrosis than in those without this feature; tumors with both coagulative and liquefactive necrosis had the highest BUdR LI (p less than 0.05). Increased vascularity was also associated with a higher BUdR LI (p less than 0.05). Although tumors with abnormal mitotic figures had a significantly higher BUdR LI than those without, the number of mitoses did not correlate with a higher BUdR LI. These results suggest that the number of mitoses is not a good indicator of tumor growth rate. Necrosis and increased vascularity should be heavily weighted in predicting the proliferative potential of individual gliomas.

Prognostic implications of the proliferative potential of low-grade astrocytomas.

The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients.

Flow cytometric determination of modal DNA population in relation to proliferative potential of human intracranial neoplasms.

Paraffin-embedded specimens of brain tumors from 256 patients who had received an intravenous infusion of bromodeoxyuridine (BUdR) at the time of craniotomy were analyzed retrospectively by flow cytometry to determine the modal deoxyribonucleic acid (DNA) population. A single G1 peak was considered to represent a unimodal DNA population; two or more G1 peaks indicated a multimodal population. Most of the pituitary tumors and moderately anaplastic astrocytomas had unimodal DNA populations, whereas a higher percentage of other slow-growing tumors, such as meningiomas, ependymomas, and neurilemmomas, had multimodal populations (46.2%, 50.0%, and 60.0%, respectively). A relatively high percentage of the rapidly growing or highly malignant brain tumors, including highly anaplastic astrocytomas, glioblastomas multiforme, metastatic tumors, and medulloblastomas, also had multimodal populations (52.9%, 48.7%, 57.1%, and 66.7%, respectively). In most tumor groups, however, the percentage of tumors with a multimodal DNA population did not correlate with the BUdR labeling index or with the percentage of BUdR-labeled S-phase cells. Thus, modal DNA analysis by flow cytometry may provide information about the degree of heterogeneity and the biological behavior of individual brain tumors, but the results do not necessarily correlate with the rate of tumor growth or the prognosis in individual patients.

Proliferative characteristics of intracranial and spinal tumors of developmental origin.

The proliferative potential of 17 intracranial and spinal tumors (six craniopharyngiomas, four chordomas, three mature teratomas, one immature teratoma, one embryonal carcinoma, one choriocarcinoma, and one dermoid tumor) was assessed. The patients received a 30-minute to 60-minute infusion of bromodeoxyuridine (BUdR) (200 mg/m2 intravenously [IV]) at the time of surgery but before a biopsy of the tumor was performed, to label cells in the DNA synthesis phase. The labeling index (LI) was calculated by determining the percentage of BUdR-labeled cells. The mean LI of the squamous epithelial elements of mature teratomas, craniopharyngiomas, and the dermoid tumor were 3.1 +/- 1.2%, 1.9 +/- 0.9%, and 2.9 +/- 1.9%, respectively. As in normal epithelium, the labeled cells were located in the basal layer. These results and the clinical findings suggest that the proliferation kinetics of these tumors are similar to those of normal skin and differ from those of rapidly growing malignant neoplasms. The other tissue elements (i.e., respiratory epithelium and cartilage) also demonstrated "organized" proliferation patterns similar to those of the corresponding normal tissues. An immature teratoma, an embryonal carcinoma, and a choriocarcinoma each had a high LI (24.6 +/- 5.3%, 32.3 +/- 3.8%, and 17.0 +/- 4.6%, respectively), and no organized pattern of proliferation was observed. In contrast, the mean LI of the four chordomas varied from 1.5% to 5.8%, and there was an even larger variation in the LI of different areas in individual tumors (from less than 1% to 7.5%). This finding suggests that even "slow-growing" chordomas sometimes can be locally aggressive and show a high incidence of recurrence, regardless of morphologic similarities.

Proliferative potential of brain metastases.

Thirteen patients with metastatic brain tumors received an intravenous infusion of bromodeoxyuridine (BUdR) 200 mg/m2 at craniotomy) to label S-phase tumor cells. Excised tumors were stained immunohistochemically for BUdR. The percentage of BUdR-positive cells was calculated to determine the BUdR labeling index (LI) (or fraction of S-phase cells), which provides an estimate of the proliferative potential. Histologically, 11 patients had adenocarcinoma (four well-differentiated, three moderately differentiated, and four poorly differentiated), one had a large cell carcinoma, and one had a small cell carcinoma. All tumors had a BUdR LI greater than 5% (mean, 13.3 +/- 7% standard deviation). Moderately and poorly differentiated adenocarcinomas had a higher LI than well-differentiated adenocarcinomas (median, 15.3% versus 8.2%). These LI values are considerably higher than those reported for primary tumors with comparable histologic features. Thus, metastatic tumors in the brain may grow faster than the primary tumors from which they originate.

The proliferative potential of human ependymomas measured by in situ bromodeoxyuridine labeling.

Twelve patients with ependymomas received a 30- to 60-minute intravenous infusion of bromodeoxyuridine (BrdU), 150 to 200 mg/m2 at surgery, to label tumor cells in the DNA synthesis phase. Labeled cells were detected in excised tumor specimens by indirect immunoperoxidase staining using anti-BrdU monoclonal antibody as the first antibody. The BrdU labeling index (LI, defined as the percentage of labeled cells in relation to the total number of cells scored) was calculated for each specimen. All four spinal cord ependymomas had a BrdU LI of less than 1%, which is consistent with our clinical experience that most such tumors grow slowly and have an excellent prognosis. Five of the eight intracranial ependymomas also had a low BrdU LI of approximately 1% or less, and three had a BrdU LI of 3.2%, 3.4%, and 4.8%. The latter three tumors, only one of which was diagnosed as a malignant ependymoma at the time of study, were either recurrent or recurred within 2 years after gross or subtotal removal. Cytologic analysis of cerebrospinal fluid (CSF) was performed in five cases; CSF seeding of tumor cells was found in only one patient, who had a malignant ependymoma. A high BrdU LI did not always correlate with CSF seeding. Measurement of the LI using BrdU and anti-BrdU monoclonal antibodies can provide more accurate information on the proliferative potential of individual tumors and may lead to a more rational grading system of ependymomas. The results of such studies do not always predict the potential for CSF seeding.

Primary cerebral angiosarcoma. Case report.

A 65-year-old man with a history of exposure to industrial solvents developed a primary cerebral angiosarcoma in the left posterior parieto-occipital lobe. The tumor had features typical of angiosarcoma on light and electron microscopy, immunohistochemical evidence of factor VIII-related antigen produced in tumor cells, and a high labeling index with bromodeoxyuridine. The relationship of angiosarcoma to toxins and viruses is discussed.

Comparison of bromodeoxyuridine labeling indices obtained from tissue sections and flow cytometry of brain tumors.

Sixteen patients with brain tumors were given a 30- to 60-minute intravenous infusion of bromodeoxyuridine (BUdR), 200 mg/sq m. Grossly viable fragments were taken from the biopsied tumor specimens and divided into two portions. One portion was dissociated into single cells, stained both with fluorescein isothiocyanate (FITC) using anti-BUdR monoclonal antibody as the first antibody and with propidium iodide (for deoxyribonucleic acid), and analyzed by flow cytometry (FCM). The labeling index (LI) was calculated as the number of FITC-labeled cells expressed as a percentage of the total number of cells analyzed. The other portion was fixed in 70% ethanol, embedded in paraffin, sectioned, and stained with immunoperoxidase using anti-BUdR monoclonal antibody as the first antibody. The LI of these tissue sections was calculated in two ways: from selected areas in which the labeled cells were evenly distributed and from the entire tissue section. The LI's obtained by FCM correlated closely with those from the entire tissue sections (r = 0.99, p less than 0.000001) and were usually lower than LI's from selected areas of tissue sections. The LI's determined by FCM also correlated well with the LI's from selected areas of tissue sections (r = 0.82, p less than 0.00012), despite the difference in values between them. Thus, the FCM-derived LI and the tissue LI can both provide useful information for predicting the biological malignancy of individual tumors and for designing treatment regimens for individual patients with brain tumors; however, different standards should be used to interpret the LI's obtained by these two methods.

Proliferative potential of vascular components in human glioblastoma multiforme.

Sixteen patients with glioblastoma multiforme received a 1-h intravenous infusion of 5-bromo-deoxyuridine (BrdU), 150-200 mg/m2 at the start of surgery, to label S-phase cells in tumor tissue. Labeled cells of vascular components and of tumor parenchyma were detected in excised tumor specimens by indirect immunoperoxidase staining using anti-BrdU monoclonal antibodies followed by periodic acid-Schiff staining. The BrdU labeling index (LI, defined as the percentage of labeled cells in relation to the total number of cells scored) was calculated separately for vascular components and tumor parenchyma in each specimen. The BrdU LI of vascular components of glioblastoma multiforme was remarkably higher than that of normal brain (1.1%-8.7% vs. less than 0.05%). The mean BrdU LIs of vascular components and tumor cells in eight primary glioblastomas were 4.5 +/- 0.8% (mean +/- SE) and 9.9 +/- 1.1%, respectively, while the corresponding BrdU LIs in eight recurrent tumors were 2.7 +/- 0.5% and 9.3 +/- 0.7%. The differences in the BrdU LIs of primary and recurrent tumors were not statistically significant, but the BrdU LI of vascular components was consistently much lower than that of tumor cells. BrdU labeling of vascular components was inconsistent and occurred mostly in glomerular-shaped vessels, but only about 20% of them contained labeled cells. These results suggest that unusual vascular proliferation, such as the formation of glomerular-shaped vessels and endothelial or adventitial proliferation, in glioblastoma multiforme may have been programmed to slow down or even to cease at a certain stage, and is not likely to be the result of neoplastic transformation.

Prediction of tumor doubling time in recurrent meningiomas. Cell kinetics studies with bromodeoxyuridine labeling.

Eight patients with recurrent meningiomas (four malignant, two hemangiopericytic, and two nonmalignant) were given intravenous bromodeoxyuridine (BUdR), 200 mg/sq m, at the time of surgery to label cells in the deoxyribonucleic acid (DNA) synthesis phase; labeled cells were detected in excised tumor specimens by immunoperoxidase staining using anti-BUdR monoclonal antibody. These tumors showed a wide range of BUdR labeling indices (LI's), calculated as the percentage of BUdR-labeled cells divided by the total number of cells scored, from 0.3% to 5.4%. The tumor doubling times (Td's), estimated from serial computerized tomography scans, ranged from 8 to 440 days and showed a close inverse correlation with the BUdR LI's. A semilogarithmic linear regression analysis of these values yielded a correlation coefficient of 0.99. Tumor doubling time (Td) can be estimated using the formula: Td = 500 X Exp (-0.73 X LI), where Exp signifies the natural log base. By predicting the growth rate of meningiomas, the BUdR LI may supplement histopathological diagnosis and improve both the determination of prognosis and the design of treatment modalities in individual patients.