Evidence for the continuity of early problem behaviors: application of a developmental model

Mitotic index > 6, proliferating cell nuclear antigen (PCNA) index > 5%, high tumour grade and absence of progesterone receptors (PR) are significant predictors for poor outcome in meningiomas. Since MIB-1 (Ki-67) is a more specific cell proliferation marker, and overexpression of TGF-alpha is also associated with tumour progression, we compared the prognostic significance of these factors with the other indices. Intracranial meningiomas from 21 men and 36 women (age 54.5 +/- 1.7, mean +/- SEM) were classified as 24 benign, 24 atypical and nine malignant. Twenty-one of the 57 tumours recurred (mean interval to recurrence was 57.3 +/- 13.1 months). The mean follow-up period for patients without tumour recurrence was 81.9 +/- 8.7 months. MIB-1 labelling index (LI) was expressed as percentage of labelled nuclei to total tumour nuclei counted in the most densely labelled areas. Analysis of variance revealed significant differences between tumour grades for MIB-1 labelling indices (0.75 +/- 0.21 for benign, 3.2 +/- 0.57 for atypical 6.04 +/- 1.48 for malignant; P < or = 0.0066), and between malignant and non-malignant meningiomas for TGF alpha staining scores (P < or = 0.029). MIB-1 LI also correlated with mitotic and PCNA indices (P < or = 0.0001), but not with age of the patients. Male patients had higher tumour MIB-1 LI than females (P < or = 0.0128). Univariate analysis indicated that MIB-1 LI > 3%, TGF alpha score > 4 (scoring scale 0-5), mitotic index > 6, and negative PR status were significant factors for worse outcome. Higher MIB-1 LI, TGF alpha score and mitotic index as continuous variables were also significant negative predictors. With multivariate analysis, both MIB-1 LI and TGF alpha score remained significant factors when paired with all other variables: TGF alpha or MIB-1 LI, respectively, mitosis, PCNA, tumour grade, PR status, age, sex, postoperative radiation therapy. We conclude that MIB-1 LI and TGF alpha score are important independent prognostic indicators for patients with meningiomas.     

Quantitative three dimensional echocardiography in patients with pulmonary hypertension and compressed left ventricles: comparison with cross sectional echocardiography and magnetic resonance imaging

Meningiomas from 40 adult patients were labeled immunohistochemically with monoclonal antibodies to bromodeoxyuridine (BUdR) and the Ki-67 antigen, MIB-1. The meningiomas were classified as classical, or benign (n = 31); atypical (n = 4); or malignant (n = 5). Meningeal sarcomas and hemangiopericytomas were excluded. The patient population consisted of 26 women and 14 men, ranging in age from 26 to 75 years. BUdR proliferation indices ranged from 0% to 5.8%, measurements that were expectedly lower than those for MIB-1, which ranged from 1.5% to 19.3%. MIB-1 proliferation indices were not significantly affected regarding steroid pretreatment or age. These results show a good correlation between the BUdR and MIB-1 proliferation markers (rs = 0.72; P < .0001), which supports the use of anti-MIB-1 as an alternative labeling tool to BUdR for the determination of the proliferation index in meningiomas, thus avoiding the administration of a potentially mutagenic drug.     

Chromosomal losses and gains in meningiomas: comparative genomic hybridization (CGH) study of the whole genome

We investigated chromosomal aberrations in meningiomas using newly developed comparative genomic hybridization (CGH) technique and compared the results with the proliferating potential of the tumors. This technique permits the entire genome to be surveyed in one session of experiments. Our results revealed chromosomal aberrations in 5 out of 10 (50%) of the tumor samples studied. Losses of the distal parts of chromosome 1p (5 out of 10) and 22q (3 out of 10) were the two most frequent chromosomal aberrations. Losses and/or gains in other regions were only sporadic. The MIB-1 staining indices (MIB-SI, %) were 1.9 +/- 0.9% (mean +/- SD) in benign (n = 8), 4.5% in atypical (n = 1), and 11.7% in anaplastic (n = 1) meningiomas. The comparison of MIB-SI between the tumors with (2.3 +/- 0.6%) and without (1.6 +/- 0.3%) chromosomal aberrations demonstrated a trend towards an increased MIB-SI in meningiomas with chromosomal aberrations (p < 0.07) by unpaired Student's t-test. This study suggests that alterations in chromosomes 1p and 22q could be a primary focus of further detailed assessment of tumorigenesis and in understanding the biological behavior of meningiomas.     

Immunohistochemical assessment of the MIB-1 Labeling Index in human hepatoblastoma and its prognostic relevance

BACKGROUND/PURPOSE: The MIB-1 monoclonal antibody has been raised against recombinant parts of the Ki-67 antigen, which is a cell cycle-related nuclear protein that is elevated in late G1 and S phases. The aim of the study was to analyze the expression pattern of MIB-1 in hepatoblastoma and to assess whether it provides any prognostic information in clinical practice. METHODS: Sections from formalin-fixed paraffin embedded tissues were collected from 18 patients who had hepatoblastoma and stained with MIB-1 antibody according to streptavidinbiotin method. A percentage score of positively stained nuclei, MIB-1 Labeling Index (LI), was determined and correlated with clinical variables. MIB-1 LI ranged from 0% to 39.5% with a mean value of 13.5%. Among them in 14 patients, who received preoperative chemotherapy, the authors analyzed the result of MIB-1 staining. RESULTS: Although there were no significant correlations between MIB-1 LI and age, sex, or histological type, a statistically significant correlation was found between clinical stage and MIB-1 LI. Mean MIB-1 LI was lower in patients with stage I and II than in those with stages III and IV (P < .05). Metastatic lesions showed higher MIB-1 LI than primary lesions, indicating that metastatic tumor cells have an increased rate of cellular proliferation. Kaplan Meier survival curve showed that patients with MIB-1 higher than 10% (n = 3) had a worse survival rate than those with lower than 10% MIB-1 LI (n = 11), whereas there was no significant difference because of the limited number of cases. Because high MIB-1 LI was correlated with clinical stage and poor survival rate, MIB-1 LI may be considered an important prognostic factor in hepatoblastoma. CONCLUSION: Although further studies, including larger series of patients, are required, the authors consider MIB-1 immunostaining an easy method to assess proliferative activity that provides useful prognostic information in hepatoblastoma.     

MIB-1 proliferation index predicts survival among patients with grade II astrocytoma

The purpose of this study was to determine whether a relationship existed between MIB-1 labeling index (LI) percentages and survival in patients with grade II astrocytomas. From archival paraffin-embedded surgical specimens of 50 patients of the University of Michigan Medical Center with World Health Organization grade II astrocytomas, 22 patients had a Ki-67 LI of less than or equal to 2.0; and 28 patients had a MIB-1 LI of more than 2.0. Over a median follow-up interval of 10 years, ranging up to 16 years, 23% (n = 5) died of tumor in the first group while 82% (n = 23) died in the second group, a distinct difference in survival between these groups. Univariate analysis showed that a high MIB-1 predicted shorter survival (p < 0.0001), and that increased age was associated with shorter survival (p = 0.007). Gender, tumor location and radiotherapy had no significant association with survival. When adjusting for these (excluding tumor location) in the Cox proportional hazards model simultaneously, MIB-1 and age were independently prognostic. The hazard ratios were 1.301 per 1% MIB-1 LI (p = 0.0001), and 1.045 per year of age (p = 0.0028). From other studies, we know that histopathologic grade and age predict survival for glioma patients. However, even within grade II astrocytomas there is still a wide heterogeneity in how long a patient survives. We conclude that among grade II astrocytomas older patients and, independently, patients with higher MIB-1 labeling index have shorter survival.     

Perceptual similarity of shapes generated from Fourier descriptors

BACKGROUND: Growth rates and tumor aggressiveness of meningiomas are thought to be closely related to brain edema development. However, histopathologic data alone are not consistently accurate predictors of the behavior and clinical course of a meningioma. METHODS: The authors examined 57 histologically proven intracranial meningiomas to identify factors, including growth fractions determined by MIB-1 immunostaining, that may influence the development of meningioma-associated peritumoral brain edema. There were 54 benign, 2 atypical, and 1 anaplastic meningiomas. The MIB-1 staining index (SI) percentage was defined as the number of MIB-1 positive cells divided by the total number of tumor cells in a 1.037-square millimeter area on the slide. The extent of peritumoral brain edema was determined using preoperative magnetic resonance imaging. The extent of edema was classified as Grade 0,1, or 2 (GR0, GR1, or GR2), in order of increasing severity. RESULTS: The MIB-1 SIs of the 57 cases ranged from 0.06-6.8% (median, 0.80%). There were 26 GR0, 20 GR1, and 11 GR2 edema cases. The MIB-1 SI rose in order of increasing edema severity. There was a statistically significant correlation between the MIB-1 SI and the extent of brain edema (P<0.0001), and also between the tumor size and the extent of brain edema (P=0.001). Meningothelial and atypical/anaplastic meningiomas were associated with peritumoral brain edema more often than any other subtype (P<0.005). CONCLUSIONS: Growth fractions, as determined by MIB-1 immunostaining, rise with increasing severity of peritumoral brain edema, indicating a close relationship between tumor aggressiveness and edema development.     

Follicular dendritic cell tumor of the mesentery

Follicular dendritic cell (FDC) tumor is an exceedingly rare malignant neoplasm and occurs mainly in the cervical lymph nodes. We report a mesenteric FDC tumor occurring in a 66-year-old female, that manifested with intraabdominal multifocal recurrence 7 years after resection of the primary tumor. Histologically, both primary and recurrent tumors were composed of oval to spindle cells with paley eosinophilic cytoplasms, indistinct cell borders, round to elongated nuclei with clear or finely dispersed chromatin, and medium to large nucleoli. Characteristically, the tumor cells were growing in sheets, fascicles, and sometimes in whorls and a storiform pattern. In addition, focal necrosis, nuclear pleomorphism and abnormal mitoses were also observed. The neoplastic cells were intimately admixed with small lymphocytes. The diagnosis was confirmed by positive immunoreactivity with CD21 and CD35 antibodies and by ultrastructural demonstration of convoluted interdigitating cell processes connected by scattered desmosome-like junctions. Although our case showed a low proliferative activity evaluated by MIB-1, multifocal recurrence has occurred. The clinicopathologic features and differential diagnosis of FDC tumors are discussed with the review of the literature.     

Postpartum onset of panic disorder

Cyclin D1 (cycD1) expression was defined immunohistochemically using monoclonal antibody DCS-6 and polyclonal antiserum H-295 in 50 glioma biopsies. The number of positive nuclei was higher for H-295 than for DCS-6, with a ratio of 3:1. The labelling index (LI) was compared to the grade of histological malignancy and to Ki-67 MIB-1 LI. The LI for cycD1 increased with histological malignancy, in parallel with the increase in MIB-1 LI. In most tumours, the maximum LI for cycD1 and MIB-1 were found in the same areas. The mean MIB-1 LI: mean cycD1 LI ratio does not vary in the three grades of astrocytic tumours. However, in this study the correlation between the two LIs was not statistically significant. Staining for cycD1 antigen does not necessarily imply that the gene is overexpressed since other molecular mechanisms can also be responsible for cell cycle deregulation. In invasive areas, the cycD1 LI is frequently higher than in solid tumour, either because more tumour cells are positive or because reactive astrocytes and activated microglia express cycD1. The relative contribution of neoplastic and reactive cells remains to be defined.     

Influenza A and Sendai viruses preferentially bind to fucosylated gangliosides with linear poly-N-acetyllactosaminyl chains from human granulocytes

Seven solitary fibrous tumors (SFTs) of the meninges are presented and their clinicopathologic features are compared with those of 64 fibrous meningiomas (FM). Patients with SFT included 5 females and 2 males age 47 to 73 years. The dura-based tumors involved the parasagittal region (1), tentorium (2), cerebellopontine angle (2), and spinal region (2). One each showed invasion of brain and of a spinal nerve root. Of four SFTs with at least 1-year follow-up, one subtotally resected example recurred. No tumors metastasized. All consisted of spindle cells disposed in fascicles between prominent, eosinophilic bands of collagen. Whorls and storiform cell arrangements were lacking. Mitoses ranged from 1 to 7/10 400 x fields. MIB-1 labeling indices ranged from 1% to 18% (mean 4%). All were PAS negative and showed strong immunoreactivity for vimentin and CD34. Of cases studied, half were estrogen and all were progesterone receptor immunopositive. The majority (72%) of FMs occurred in females and most (72%) were supratentorial. Recurrence was noted in 15%. Mitotic activity varied from 0 to 3 mitoses per 10 400 x fields (mean < 1). MIB-1 labeling indices ranged from 1% to 5% (mean 1.5%). Unlike SFT, FMs were glycogen-containing and variously exhibited a storiform pattern (13 of 20), psammoma body formation (9 of 20), and calcification of collagen (4 of 20). Immunoreactivities included vimentin (100%), focal to patchy EMA (80%), S-100 protein (80%), collagen IV (25%), and patchy, mild-to-moderate CD34 staining (60%). Of cases studied, nearly half were estrogen and all were progesterone receptor staining positive. Meningeal SFTs represent a distinct morphologic entity, the morphologic and immunohistochemical features of which differ from those of FM and suggest a histogenetic relationship to pleural SFT. Although a minority histologically appear to be low grade malignant, our limited experience suggests that they behave in a benign fashion. The classification of mesenchymal tumors affecting the central nervous system must be expanded to include SFT.     

Cytogenetic analysis of aggressive meningiomas: possible diagnostic and prognostic implications

BACKGROUND: Published karyotypes from aggressive (atypical and malignant) meningiomas are few, but suggest clonal evolution from benign tumors with monosomy 22 to aggressive forms with additional abnormalities. The goal of this study was to identify the most frequent karyotypic abnormalities associated with aggressive histopathology and biologic behavior. METHODS: Eight intracranial meningiomas exhibiting histologically atypical features at the time of intraoperative diagnosis were chosen for cytogenetic analysis. The study set was comprised entirely of histologically atypical meningiomas. Four were considered malignant; three on the basis of brain invasion and one due to extracranial metastases. None was histologically anaplastic. RESULTS: Chromosomal abnormalities were demonstrated in 6 cases (75%), 5 of which were complex (63%). Loss of chromosome 22 was identified in two cases, both of which were associated with additional aberrations. Abnormalities most frequently involved chromosomes 1 (63%), 3 (50%), and 6 (63%). Four cases (50%) had dicentric or ring chromosomes. An additional 47 previously reported karyotypes from atypical and malignant meningiomas were reviewed. Comparison with published karyotypes of 200 histologically benign meningiomas served to underscore the increased frequency of complex karyotypes, chromosome 1, 3, and 6 abnormalities, and telomeric associations in the aggressive tumors. Apparently normal karyotypes as well as monosomy 22 alone were more frequently associated with benign, nonatypical histopathology. CONCLUSIONS: These findings suggest a possible role for cytogenetic analysis in determining the prognosis and perhaps in refining the diagnosis of atypical or aggressive meningiomas. Further studies are necessary to determine the significance of complex karyotypes, chromosome 1, 3, and 6 abnormalities, and telomeric associations, particularly whether they portend a more aggressive clinical course in meningiomas lacking features of histologic atypia.     

Fine needle aspiration biopsy of breast carcinoma in pregnancy and lactation

OBJECTIVE: To delineate the cytomorphologic features seen in cancer of the breast during pregnancy and lactation, to compare them to the cytomorphologic parameters in benign conditions and to determine the feasibility of differentiating features of malignant breast carcinoma from those of benign breast lesions during pregnancy. STUDY DESIGN: The study group consisted of pregnant or lactating women with breast carcinoma and with benign breast lesions who underwent fine needle aspiration (FNA) of the breast lesions. The findings of FNA were reviewed, analyzed, tabulated and correlated with the pathologic diagnosis of the breast biopsies. RESULTS: Eleven patients had malignant cytomorphologic changes, including increased cellularity, multilayering, enlarged and pleomorphic nuclei, single or multiple nucleoli, mitosis and numerous isolated tumor cells. Secretory changes were scanty. The background was foamy and necrotic. FNA of the benign lesions showed a biphasic cell pattern with cohesion; minimal nuclear pleomorphism; single, regular nucleoli; and naked nuclei in a granular background with foamy macrophages. Increased cellularity with nuclear atypia, single cells and a dirty background was seen in benign and malignant conditions. CONCLUSION: The main cytologic features that differentiate breast carcinoma from benign conditions during pregnancy and lactation are crowding and overlapping of nuclei, dyscohesion and enlarged, pleomorphic nuclei with irregular nuclear membranes, coarse nuclear chromatin and mitoses. Pregnancy-related hyperplastic changes with atypia can potentially result in a false positive diagnosis of carcinoma.     

Allelic losses on chromosomes 14, 10, and 1 in atypical and malignant meningiomas: a genetic model of meningioma progression

To investigate chromosomal events that underlie formation and progression of meningiomas, we have examined a set of 18 benign (WHO grade I), 15 atypical (grade II), and 13 anaplastic/malignant (grade III) meningiomas for loss of heterozygosity (LOH) on chromosomes 1p, 6p, 9q, 10q, and 14q. Frequent loss of loci on these chromosomes was seen in grade II and grade III tumors, specifically, 14q (II and III, 47 and 55%), 1p (40 and 70%), and 10q (27 and 40%). In contrast, LOH for these loci was infrequent in benign meningiomas, specifically, 14q (0%), 1p (11%), and 10q (12%). The smallest common regions of deletion that could be defined were 14q24-q32, 1p32-pter, and 10q24-qter. These observations indicate the likely presence of tumor suppressor genes in these regions that are involved in the development of WHO grade II and grade III meningiomas. Because LOH for loci on chromosomes 1p and 10q was found in tumors of all grades and because the frequency of LOH in all three regions increased with tumor grade, these results would support a model for the formation of aggressive meningiomas through tumor progression.     

Epidermal growth factor receptor and labeling index are independent prognostic factors in glial tumor outcome

The aim of this study was to perform a multivariate analysis including clinical and biological prognostic factors on glial tumor outcome. Seventy-nine patients were analyzed (48 men and 31 women; mean age = 56 years, range = 16-77 years): 7 had a benign glial tumor (grades 1 and 2), 21 had an anaplastic glial tumor (grade 3), and 51 had a glioblastoma (grade 4). Median follow-up was 17.9 months for patients who survived (50 patients died). Biopsies were obtained at time of diagnosis (complete tumor resection in 62 patients and stereotaxic biopsies in 17 patients). Epidermal growth factor receptor (EGFR) was measured by a binding assay, and labeling index (LI) was measured by tritiated thymidine incorporation. EGFR varied from 4 to 73,110 fmol/mg protein (mean = 3912 fmol/mg protein; median = 374 fmol/mg protein; n = 79). LI varied between 0.1 and 16.5% (mean = 6.2%; median = 5.2%; n = 40). Log10 EGFR was significantly and positively correlated with patient age. LI was significantly different according to tumor histology. Univariate Cox analysis (end point was cancer death) showed that age (P = 0.027), log10 EGFR (P = 0.025), and LI (P = 0.0019) were significant continuous variables, the survival being shortened when the covariable increased; tumor resection (P = 0.015, relative risk = 0.45) and histology (P = 0.0009) were significant categorical factors. A multivariate Cox analysis (forward selection) including age, histology, tumor resection, log10 EGFR, and LI revealed that log10 EGFR, LI, and tumor resection were the only independent significant predictors of survival. This multivariate approach reveals that the clinical prognostic factors of glial tumors, namely age and tumor histology, disappear, to the benefit of intrinsic characteristics of the tumor, i.e., EGFR expression and LI, suggesting that coupled EGFR and LI determination could be a useful tool for better evaluation of glial tumor outcome.     

"Rhabdoid" meningioma: an aggressive variant

It is has been suggested that rhabdoid morphology is associated with a poor prognosis, regardless of tumor histogenesis. We report a series of 15 meningiomas with rhabdoid features. Nine patients had undergone multiple resections. In six, the rhabdoid component was histologically apparent only in recurrences. Rhabdoid morphology was defined as sheets of loosely cohesive cells with eccentric nuclei and hyaline, paranuclear inclusions. Ultrastructurally, the latter consisted of whorls of intermediate filaments often entrapping lysosomes or other organelles. Meningothelial features included whorl formation and nuclear pseudoinclusions, immunohistochemical coexpression of vimentin and epithelial membrane antigen, and the ultrastructural finding of interdigitating cell membranes and intercellular junctions. At the histologic level, a conventional meningioma component was noted in most tumors; only four lesions were entirely rhabdoid. Histologic malignancy (brain invasion or anaplasia) was observed in nine cases, another two tumors being considered malignant on the basis of extracranial metastasis. In the majority, increased cell proliferation was evidenced by a high mitotic rate or MIB-1 LI. At last follow-up, 13 patients (87%) had experienced at least one recurrence and 8 (53%) were dead of disease. Median time to death was 5.8 years after initial surgery and 3.1 years after the first appearance of rhabdoid morphology. Our findings corroborate those from a smaller series recently reported by Kepes et al. on the same entity (Kepes JJ, Moral LA, Wilkinson SB, Abdullah A, Llena JF. Rhabdoid transformation of tumor cells in meningiomas: A histologic indication of increased proliferative activity. Report of four cases. Am J Surg Pathol 1998;22:231-8). They further suggest that rhabdoid meningiomas are highly aggressive tumors and that the rhabdoid phenotype represents a marker of malignant transformation in meningiomas.     

Effects of gamma knife radiosurgery for brain tumors: clinical evaluation

BACKGROUND: Gamma knife radiosurgery is a safe and effective alternative to microsurgery in the management of selected intracranial lesions. In our initial three-year experience with gamma knife radiosurgery, 431 patients were treated using this method. This report presents the treatment results for three different types of brain tumors: benign meningiomas, malignant metastases and gliomas. METHODS: A retrospective study was performed to analyze a consecutive series of 71 meningiomas, 31 metastatic tumors and 21 gliomas treated by gamma knife radiosurgery between March 1993 and May 1996. The treatment results were investigated using regular magnetic resonance examinations and tumor volume measurement at six-month intervals to observe sequential changes of the tumors. Patients with meningiomas were further divided into three groups according to the peripheral radiation doses: high-dose (20-17 Gy, n = 18), medium-dose (16-15 Gy, n = 33) and low-dose (14-12 Gy, n = 20). The Generalized Estimation Equation was applied to compare treatment results in these three groups with different doses and tumor volumes. RESULTS: Volume measurements of the 71 meningiomas showed that 76% decreased in size, 16% stabilized and 8% increased in size. The volumes increased most frequently in the early stage (6-12 months) after treatment and subsequently regressed after the twelfth month. The tumor control rate for meningiomas in our three-year follow-up was over 90%. For meningiomas, the statistical analysis showed that both the radiation dose and tumor volume were significantly related to the development of adverse radiation effects (p < 0.05). In metastatic tumors, rapid tumor regression after radiosurgery was found in 87% of the patients. In gliomas, radiosurgery effectively inhibited tumor growth in selected patients with small, circumscribed, less infiltrative tumors. Ependymomas and low-grade astrocytomas had more favorable outcomes than other gliomas. CONCLUSIONS: Gamma knife radiosurgery is effective for controlling tumor growth in benign meningiomas for up to three years after surgery. In selected cases of malignant metastasis and gliomas, most patients appeared to benefit from the treatment with symptomatic improvement and prolonged survival. Treatment strategy and dose selection in radiosurgery should be adjusted to optimize tumor control and avoid adverse radiation effects.     

Meningiomas. Epidemiological and anatomopathological study of 340 cases

The authors have retrospectively reviewed all tumors of central nervous system (CNS) operated at the most important neurosurgery hospitals of Curitiba in a 5-year period (1990-1994) and found 304 (22.4%) cases of meningioma. Age mean of the patients was 48.5 years, with a range of 3 to 90 years. A marked female preponderance (68.7%) was noted. The most common tumor location was brain (n = 280) and the remaining cases occurred in spinal cord (n = 10), cerebellum (n = 9) and cranial nerves (n = 5). Histologically, there were 294 (96.7%) meningiomas of the classical type, six malignant or anaplastic, three atypical and one papillary. Two hundred and sixty seven classical meningiomas were from the meningotelial subtype, ten psamomatousos, five fibroblastic, five microcystic, five transicional and two angiomatous. The authors conclude that meningiomas are one of the most common group of primary neoplasias of CNS and the definition of malignancy in those tumors is beset by frequent discordance between histologic and biologic features.     

p53 accumulation and apoptosis in embolized meningiomas

Preoperative embolization of meningiomas is performed to decrease blood loss at surgery. While it is also expected to reduce tumor recurrence by producing necrosis at the site of dural attachment, very little has been described about what happens to the non-necrotic tumor cells. We investigated how the proliferative activities of meningiomas were modified after embolization. In nine meningiomas which were embolized preoperatively, proliferative potentials and expression of cell cycle inhibitors were assessed immunohistochemically using MIB-1, anti-53 (DO-1 and DO-7), and anti-p21 (WAF1/CIP1) monoclonal antibodies. To determine whether a cell underwent apoptotic death besides necrosis, we applied the terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling method. Results were compared with control meningiomas without embolization. MIB-1 positive cells often gathered in perinecrotic areas, although the mean MIB-1 staining index of the embolized meningiomas was not significantly different from the control. p53 and its downstream effector p21 accumulated mainly in the perinecrotic areas in eight of the nine embolized meningiomas. Apoptosis was also observed in the concomitant areas. Double staining for both MIB-1 and p21 frequently showed positive cells for both antibodies. The accumulation of MIB-1 positive cells in the embolized meningiomas may not be a sign of fast growth or malignancy, but it may implicate arrest of cell cycle by the p21. This study indicates that embolized meningiomas exhibit not only necrosis but also apoptosis and cell cycle arrest. The latter effects appear to be at least partly p53 dependent.     

Proliferation and DNA fragmentation in meningioma subtypes

Atypical meningioma has been introduced as tumour subtype of intermediate biological behaviour between classical and malignant meningiomas. To substantiate this three-step scale of malignancy, we assessed the proliferative activity reflected by Ki-67 (MIB1) labelling index (LI) in a series of 89 meningiomas, including 15 classical, 29 atypical, 35 anaplastic tumours, and 10 haemangiopericytomas and papillary meningiomas. The possible correlation of proliferation with the frequency of apoptosis and their relations to BCL-2 immunoexpression was investigated in seven classical, 10 atypical and 10 malignant meningiomas. Apoptosis was demonstrated by evaluation of the frequency of apoptotic figures, by the enzymatic technique of in situ tailing (IST) which stains apoptotic DNA fragments, and by DNA preparation and gel electrophoresis demonstrating DNA laddering in frozen tissues of five meningiomas. MIB1 LI revealed a highly significant increase from classical through atypical to anaplastic meningiomas (P < 0.0001); haemangiopericytomas and papillary meningiomas were well within the range of atypical meningiomas. IST indices rose with increasing malignancy and correlated with MIB1 LI (P < 0.0001): they showed a weak inverse correlation with BCL-2 immunoexpression (P = 0.05). BCL-2 expression tended to decrease with malignancy grade and was unrelated to MIB1 LI or frequency of apoptosis. Our data show that (i) apoptosis is a feature of meningiomas, significantly correlated with the malignancy scale. (ii) DNA fragmentation shows significant correlation with proliferation and inversely with BCL-2 expression; (iii) proliferation indices and frequencies of apoptosis/DNA fragmentation within meningioma subgroups corroborate the intermediate biological position of the atypical meningioma between classical and malignant meningiomas.     

Recurrence of meningiomas versus proliferating cell nuclear antigen (PCNA) positivity and AgNOR counting

Meningiomas have a wide range of biological potential and clinical behaviour. Histological findings are helpful in recognizing the malignant potential but often fail to correlate with clinical behaviour. This study attempts to correlate the silver nucleolar organizer regions (AgNORs) and proliferating cell nuclear antigen (PCNA) with clinicopathological features of biological activity. Thirty-four completely resected meningiomas were classified as benign [19], atypical [6] and malignant [9]. Forty-eight initial and recurrent tumour materials were investigated for staining of AgNORs and immunohistochemistry using monoclonal antibodies against PCNA (clone 19A2 and PC10). There were no difference between the recurrent and non-recurrent cases with regards to AgNOR, PC10 and 19A2 values. Also, no significant difference was found between the primary and recurrent tumours. Both PC10 and 19A2 labelling indices (LI) showed a significant difference between benign and malignant meningiomas. The 19A2 LI was 0.56 +/- 0.21 in benign and 2.45 +/- 16 in atypical meningiomas. The 19 A2 counts showed significant difference between benign and atypical tumours but PC10 values failed to show such a correlation AgNOR and PCNA indices were not found to be useful in predicting recurrences compared to the surgical procedure and histopathological criteria.     

Cell kinetics of head and neck cancers

We measured the tumor cell proliferative rate in 26 patients with head and neck cancer, 22 of which were squamous cell carcinomas (SCCs). Patients received sequential infusions of iododeoxyuridine and bromodeoxyuridine, after which the tumor was biopsied and studied. The percentage of labeled cells [labeling index (LI)] in well-differentiated SCCs was 20.4 +/- 2.7% (mean +/- SE) and 23.8 +/- 2.1% in moderately differentiated SCCs (P = 0.135). The LIs of two poorly differentiated SCCs were 39.4 and 55.9%. The LI was 2.5% in a high-grade lymphoepithelioma and 24.8% in a malignant lymphoma. In one well-differentiated and one poorly differentiated mucoepidermoid tumor, the LIs were 3.0% and 29.1%, respectively. S-phase duration time measurements ranged from 5.1-21.5 h (12.8 +/- 1.5). The calculated potential doubling times ranged from 18.8-84.5 h (47.3 +/- 6.7). The duration of G2 was between 90 and 180 min. To track the fate of labeled cells, in four patients a repeat biopsy was obtained 7-14 days after the iododeoxyuridine/bromodeoxyuridine infusion. These patients did not receive treatment between the biopsies. Due to the dilution of the label, most labeled cells in the second biopsy demonstrated a "fragmented" pattern resulting from repeated cell divisions. In two patients, however, 25% of cells in the second biopsy had undiluted label, suggesting that these cells had not divided after incorporating iododeoxyuridine/bromodeoxyuridine. On Day 7 labeled cells migrated to keratinized parts of tumors and to necrotic foci. Thus, the arrest of cell cycle transition, tumor cell differentiation, and cell death may be major routes of tumor cell loss from the proliferative compartment. This may explain the difference between very short potential doubling times and the actual rate of tumor growth.