Brain-tumor cell kinetics correlated with survival

Cell Kinetics Aspects of Human Malignant Neuroepithelial Tumors: A Follow-Up Study

The prognostic value of proliferative activity and DNA distribution (ploidy), determined by flow cytometry (FCM), was evaluated in 38 cases of human malignant neuroepithelial tumors. No statistically significant correlation was found between flow cytometric data and clinical outcome. In particular, there was no significant difference between mean survival in cases with percentage of cells in S-phase lower and higher than 5%, respectively. In 21 cases with unimodal DNA distribution, the mean survival was 11.7 months; in 17 cases with bimodal DNA distribution, the mean survival was 12.5 months. The difference was not statistically significant. In our experience, proliferative activity and ploidy do not correlate well with the clinical course and survival of patients with malignant neuroepithelial tumors. However, application of FCM may provide, aside from histopathologic examination, additional biologic information that may be valuable in understanding the variation observed in the course of individual patients.

Role of MIB1 in predicting survival in patients with glioblastomas

BACKGROUND

Histologic immunomarkers of cell cycle proteins have been utilized for prognosis in high-grade astrocytic tumors. One such marker, MIB1, an antibody immunoreactive throughout the cell cycle, is predictive of more aggressive disease and poorer prognosis in astrocytomas. An independent role of MIB1 analysis for survival prediction and clinical management within histologic grades has not been clearly proven.

METHODS

This study retrospectively evaluated MIB1 reactivity in tissue samples from 116 patients with glioblastomas on initial medical presentation. Clinical variables considered included gender, age, Karnofsky Performance Scores (KPS), extent of surgical resection, adjuvant radiation and survival.

RESULTS

Univariate and multivariate analyses were used to correlate these variables with MIB1 staining. MIB1 staining does not predict overall survival or response to adjuvant therapy as an independent risk factor.

CONCLUSION

MIB1 labeling does not predict patient survival as an independent variable and does not predict response to additional therapies. Patient survival with glioblastoma was predicted by KPS, age, extent of resection and use of adjuvant radiotherapy.

Glioblastomatous transformation of ganglioglioma: Case report with reference to molecular genetic and flow cytometric analysis

Gangliogliomas generally behave as benign indolent tumors. However, gangliogliomas undergoing malignant transformation have also been reported. The molecular basis for the malignant transformation of gangliogliomas remains unclear. We describe a case of ganglioglioma, which had transformed to glioblastoma after the gross total resection of the original tumor, in a 4-year-old girl. The present case is unusual in four aspects: (i) it arose from a low-grade ganglioglioma in the absence of previous radiation or chemotherapy, which is the fourth reported case; (ii) the original tumor showed a high proliferative index on flow cytometry but a low Ki-67 labeling index, implying that the application of flow cytometry might play a certain role in predicting biological and clinical behavior of low grade gangliogliomas; (iii) p53 mutation and deletion appeared in the secondary glioblastoma, which was not shown in the original well-differentiated ganglioglioma; and (iv) the transformed glioblastoma showed p16 inactivation detected by methylation and deletion, which are relatively uncommon genetic events in secondary glioblastomas. This is the first report of a genetic alteration in glioblastoma arising from a well differentiated ganglioglioma prior to radiation or chemotherapy. Based on the above findings, irrespective of radiotherapy or chemotherapy, rare recurrence of malignant evolution, especially tumors of high S-phase fraction on flow cytometry, warrants long-term follow-up, even in a well-differentiated ganglioglioma.

DNA topoisomerase IIalpha expression correlates with cell proliferation but not with recurrence in intracranial meningiomas

AIMS

To assess the value of topoisomerase IIalpha (TopoIIalpha) as a novel proliferation-associated molecule, by correlating its immunohistochemical expression with Ki67 (MIB-1), cell proliferating cell nuclear antigen (PCNA) and mitotic index in meningiomas. Furthermore, to investigate its relation to standard clinicopathological parameters and patients' outcome.

METHODS AND RESULTS

This retrospective study comprised a consecutive series of 57 patients with primary intracranial benign and atypical meningiomas. Six tumours recurred (10.5%) following complete surgical resection, within a follow-up period ranging from 21 to 108 months (median 60 months). Archival formalin-fixed paraffin-embedded sections were stained with standard immunohistochemical methods. The lower proliferation indices were obtained with TopoIIalpha and the higher ones with PCNA. TopoIIalpha labelling index (LI) ranged from 0.1% to 10% (median 0.5%) and, along with Ki67 and PCNA LI, increased with malignancy grade (P=0.049, P=0.045 and P < 0.001, respectively), displaying though a significant overlapping between grades. A significant positive correlation was shown between TopoIIalpha and Ki67 (P < 0.001) or PCNA (P=0.032). In univariate and multivariate survival analysis, TopoIIalpha failed to predict meningioma recurrence and did not affect disease-free survival. Only tumour size and Ki67 LI provided significant prognostic information in this regard.

CONCLUSIONS

TopoIIalpha expression may be useful as a novel proliferation marker in meningiomas, presenting several advantages over the markers currently in use, notably providing a better estimate of the number of cycling cells and a more uniform nuclear staining pattern. However, it fails to discriminate between benign and atypical neoplasms and does not provide prognostic information beyond that obtained by Ki67.

Prognostic significance of endothelial surface score and MIB-1 labeling index in glioblastoma

The aim of this study is to investigate the usefulness of a vascular endothelial surface score (VESS) and MIB-1 labeling index (MIB-1 LI), in a defined series of glioblastomas, as biological markers with prognostic significance of survival. Tumor tissue and survival were studied in a series of 38 patients with glioblastoma, previously treated by surgical resection and radiotherapy. For each tumor, immunohistochemical and morphometric studies were performed in order to study MIB-1 LI, and VESS, expressed as the CD-34 immunostained endothelial surface per 1000 tumor cells. The survival for the entire patient population of the series was 48.1+/-14.1 weeks, and the mean VESS for the tumors of the series ranged from 16.7 to 107 microm2 per 1000 tumor cells (mean: 38.7+/-18.2). Factors such as age or MIB-1 LI were not significatively associated with survival, but the median survival for the 18 patients with a VESS less than 35 was 50.7+/-3.7 weeks, versus 45.9+/-2.8 weeks for the 20 patients showing a VESS higher than 36 (p < 0.05). Our present results suggest that tumor VESS, expressed as the CD-34 immunostained endothelial surface per each 1000 tumor cells, may have usefulness, as angiogenic-related factor influencing survival, in patients with glioblastoma.

Bromodeoxyuridine labeling index in glioblastoma multiforme: relation to radiation response, age, and survival

PURPOSE

Various measures of the rate of tumor cell proliferation have been found to predict survival in patients with intracerebral gliomas. We correlated the bromodeoxyuridine labeling index (BrdUrd LI) with the response to radiation therapy, survival, and known prognostic factors in a series of patients with glioblastoma multiforme (GM) to test its utility as a prognostic factor.

METHODS AND MATERIALS

The BrdUrd LI was determined in 200 newly diagnosed intracranial GMs. Age and sex were known for all patients. The response to radiation therapy was determined in 116 patients by comparing neuroimaging studies obtained before and after external beam radiation therapy. Survival was analyzed in 64 patients who were treated according to two consecutive prospective clinical protocols.

RESULTS

The median BrdUrd LI was 6.5% (mean, 7.2%; range, 1.1-25.4%). The BrdUrd LI did not correlate significantly with age, sex, radiation response, or survival. Age and Karnofsky performance score were independent prognostic factors in our cohort.

CONCLUSION

The proliferative rate as measured by BrdUrd LI was not a prognostic factor in our GM cohort. The BrdUrd LI did not correlate significantly with known prognostic factors in GM. There was no significant relationship between BrdUrd LI and radiation response.

Low-grade glial tumors in basal ganglia and thalamus: natural history and biological reappraisal

The natural history of 70 patients affected by low-grade astrocytomas was recorded after the histological diagnosis was obtained by serial stereotactic biopsy. Forty-three percent of these patients died within 3 years. The value of cell kinetics assessment at the time of stereotactic biopsy was investigated, and the labeling index percent may be considered the most accurate prognostic factor in these histologically homogeneous astrocytomas. It has been confirmed that the young age of patients predicts a more favorable course, but the value of this also seems to be linked to and dependent on cell kinetics. These data are discussed in view of the opportunity to perform more aggressive "cytoreductive" treatments in deep brain tumors when these indices support an expected poor prognosis.

Prognostic significance of proliferating cell nuclear antigen (PCNA) expression in gliomas

The relationship between proliferating cell nuclear antigen (PCNA) expression and various clinicopathological indices (age, sex, tumour location, histological type and grade and treatment) and post-operative survival were studied in patients with central nervous system gliomas using univariate and multivariate analysis. The expression of PCNA (PC10 score) was examined immunohistochemically using the monoclonal antibody PC10 on paraffin sections from 45 cases. Univariate analysis showed that a high PC10 score as well as older age, high histological grade and the histological type (astrocytoma) were associated with reduced survival. However, multivariate analysis revealed that only PC10 score and histological type had independent prognostic significance. The most important feature influencing PC10 score was the tumour grade. Regarding the patients who relapsed, the survival from the time of original diagnosis was related to the relapse-free period, while the PC10 score of the primary tumour emerged as the only independent predictor of survival following the first recurrence. These results indicate that PCNA expression is an independent prognostic indicator in CNS gliomas.

Prognostic significance of bromodeoxyuridine labeling in primary and recurrent glioblastoma multiforme

To evaluate the prognostic significance of bromodeoxyuridine (BUdR) labeling index (LI) and to estimate tumor proliferative potential, BUdR LI was examined in 98 patients having a primary diagnosis of glioblastoma multiforme (GBM); 55 underwent infusion of 200 mg/m2 of BUdR at the time of the primary resection and 49 underwent infusion at the time of the second resection. The tumors of six patients were labeled at both operations. The tumor specimens were stained with hematoxylin and eosin for histopathology and by immunohistochemical methods to determine the ratio of labeled to unlabeled cells, i.e., BUdR LI. The median BUdR LIs for the primary and recurrent GBM were significantly different at 6.8 and 2.6%, respectively (P < 0.0001). However, there was no significant association between BUdR LI at the first or second operation and survival (log rank, P = 0.12; Cox regression analysis, P = 0.91; log rank, P = 0.55; Cox regression analysis, P = 0.17, respectively). Patients who underwent a second operation within 10 months of the first operation had a lower BUdR LI than did patients with a longer interval between procedures (P = 0.078; Spearman rank correlation, 0.26). The aggressive biological behavior of GBM is dependent on complex cellular kinetics, not simply on the number of cells within the S phase of the cell cycle. Caution should be used when determining prognosis with BUdR LI in GBM.

DNA index and S-phase in primary brain tumors. A comparison between fresh and deparaffinized specimens studied by flow cytometry

Forty-nine primary intracranial tumors (33 astrocytomas, eight acoustic schwannomas, five oligodendrogliomas, and three miscellaneous tumors) were studied by flow cytometry. Each tumor specimen was divided into two portions: one was studied as an unfixed suspension stained with propidium iodide and the other after formalin fixation and paraffin embedding. The 50-microns sections from the paraffin blocks were deparaffinized, rehydrated, and enzymatically disintegrated, and the cells in suspension were stained with propidium iodide. Flow cytometry of the two portions showed a significant correlation between fresh and fixed specimens regarding the S-phase (r = 0.87) and a very close correlation fo the deoxyribonucleic acid (DNA) index (r = 0.95). When the 33 astrocytomas were analyzed separately, similar results were obtained (r = 0.86 for S-phase and r = 0.93 for DNA index, respectively). This study demonstrated a high correlation between fresh and fixed specimens for DNA ploidy and S-phase both in primary intracranial tumors in general and also in the selected subgroup of astrocytomas.

The effect of radiation on normal human CNS as detected by NMR spectroscopy

In a prospective study, proton (1H) and phosphorus (31P) nuclear magnetic resonance spectroscopy were used to search for effects of brain tumor radiotherapy on normal human central nervous system. Phosphorus spectroscopy data at 1.5 T seems to suggest that any radiation induced damage that may occur as a result of therapeutic brain irradiation, does not alter the relative concentrations of phosphorus metabolites or the intracellular pH beyond the limits of normal variation (approximately +/- 20%). Proton spectroscopy, on the other hand, detects post radiation changes in the ratios of certain nuclear magnetic resonance visible metabolites following radiotherapy, particularly choline/N-acetylaspartate, and especially in regions of brain receiving high doses of radiation. Such changes may be indicative of the release of membrane bound choline during radiation induced demyelination of brain. Of interest, we have found elevated metabolite ratios of 31P in normal central nervous system prior to radiotherapy, which persisted throughout the time span of the study in both the ipsilateral and contralateral cerebral hemispheres.

Prediction of recurrence in pituitary tumours: a flow cytometric study using in vivo bromodeoxyuridine

Although most pituitary tumours are regarded as benign, there is a significant risk of local recurrence and a few are frankly malignant. The prediction of clinically aggressive behaviour by histopathological means is inadequate and the selection of patients for postoperative radiotherapy has often been empirical. The flow cytometric analysis of the DNA content of certain intracranial tumours has suggested a correlation between a high proliferative index and a tendency to recur. The in vivo administration of bromodeoxyuridine (BUdR) yields a reliable and accurate S-phase labelling index and evaluation by flow cytometry allows a much greater and therefore more representative number of cells to be examined. We report our results for the flow cytometric evaluation of the S-phase fraction in a group of 11 human pituitary tumours following the preoperative administration of BUdR and discuss the correlation between high values of S-phase fraction and clinically aggressive behaviour. Initial results suggest a correlation between radiological evidence of tumour invasion and an S-phase greater than 2%.

Immunohistochemical demonstration of proliferating cell nuclear antigen in glioblastomas: pronounced heterogeneity and lack of prognostic significance

In order to evaluate a possible significance of the expression of proliferating cell nuclear antigen (PCNA) as clinically useful prognostic parameter, we retrospectively investigated a series of 40 glioblastomas by means of immunohistochemistry and compared the results to patient survival. All glioblastomas included in the study had been treated by operation, radiotherapy and intraarterial ACNU [3-(4-amino-2-methyl-5-pyrimidinylmethyl)-1-(2-chloroethyl)-1-nitr osourea] chemotherapy. Patient survival ranged from 2 months to 42 months (mean: 14.2 months). PCNA values varied widely, ranging from 0.5% to 75% (mean: 24.9%). Statistical analysis revealed no significant correlation between PCNA index and patient survival. Our study thus indicates that the expression of PCNA appears not to be a useful prognostic parameter for glioblastoma patients.

Pituitary adenoma proliferative indices and risk of recurrence

Twenty unselected pituitary adenomas have been examined for proliferative indices (PIs), and anterior pituitary hormone expression. All but two of the tumours were non-functional with proliferative indices from less than 0.1 to 0.5%. Two tumours were null cell adenomas with PIs less than 0.1 and 0.2%. The PIs of the three recurrent tumours was less than 1.0%. Gonadotrophin and TSH immunoreactivity was heterogenous and was found in 12/20 (60%) of the tumours. There was no significant relationship between PI, hormone expression or any other measured parameter. The biological behaviour of pituitary adenomas with a PI of less than 0.1% is uncertain, but those with a PI of greater than 0.1% are more likely to recur although longer follow-up is needed to confirm this.

Prognostic significance of nuclear DNA content in human neuroepithelial tumors

The relationship between survival and flow cytometric DNA-ploidy and other prognostic factors such as histological subtype, anatomical tumor site, patient sex and age was investigated in 153 patients with intracranial neuroepithelial tumors who underwent surgical treatment. We found a trend toward poorer survival from anaplastic astrocytomas and glioblastomas with respect to low-grade (I and II) astrocytomas (which did not differ significantly); accordingly, patients were grouped into these 3 histologic subgroups. Thirty-seven of the 153 tumors (24.2%) were aneuploid with a median DNA-index (DI) of 1.3 (range: 1.2-2.0). DNA-ploidy correlated with histology, since anaplastic astrocytomas and glioblastomas were significantly (p = 0.041) more frequently aneuploid (around 30%) than low-grade astrocytomas (around 10%). Patients with DNA-aneuploid tumors (i.e., with DI not equal to 1.00) survived for a shorter time (31.4 weeks) than patients with DNA diploid tumors (75.1 weeks) (p less than 0.001). This difference was confirmed by Cox's multivariate analysis. Aneuploid tumors were associated with a poorer survival (p = .0002) when compared with diploid tumors, resulting in a relative risk point estimate (RR) of 2.41, 95% confidence interval (Cl) = 1.55-3.74. Histological subtype was also significantly associated with survival (p less than 0.0001), with RRs of 2.09, 95% Cl = 1.13-3.86 and 3.59, 95% Cl = 1.96-6.59 for anaplastic astrocytomas and glioblastomas, respectively, compared to low-grade astrocytomas. We therefore suggest that the flow cytometric measurement of DNA-ploidy has relevant significance in predicting survival in patients treated for intracranial neuroepithelial tumors.

Early prognosis of supratentorial grade 2 astrocytomas in adult patients after resection or stereotactic biopsy. An analysis of 50 cases operated on between 1984 and 1988

50 adult supratentorial low-grade astrocytomas operated upon between 1984 and 1988 were analysed retrospectively with respect to postoperative condition and progression-free survival. Pilocytic lesions were excluded. In 32 instances the tumour was macroscopically completely removed and partially in 4. In 14 cases a stereotactic biopsy was performed only. 10 patients received postoperative radiotherapy with 55 to 65 Gy. 1 patient died perioperatively from pulmonary embolism. 39 patients could resume their previous activities after discharge from the hospital, 10 were significantly disabled by neurological deficit, reduced neuropsychological performance or medically intractable epilepsy. Postoperatively, most patients required continuous anti-epileptic medication, 10 recurrences or tumour progressions of incompletely removed or merely biopsied lesions were observed within the mean follow-up period of 22 months. All recurrences after gross total removal, that were reoperated, had progressed to a malignant glioma. Of the prognostic tumour characteristics analysed, a histologically well-delineated tumour demarcation was most clearly associated with a favourable prognosis. Concerning treatment modalities, gross total resection was associated with a favourable prognosis. Radiotherapy was associated with an unfavourable outcome but this is probably due to selection of otherwise unfavourable cases.

In situ analysis of cell kinetics in human brain tumors. A comparative immunocytochemical study of S phase cells by a new in vitro bromodeoxyuridine-labeling technique, and of proliferating pool cells by monoclonal antibody Ki-67

A newly developed in vitro labeling method with bromodeoxyuridine (BrdU) identifies S phase cells in situ in freshly obtained surgical tissue of human brain tumors which is subsequently fixed and embedded in paraffin for BrdU immunovisualization. For the first time, the BrdU labeling index (LI) is successfully compared here with the LI obtained by immunostaining of frozen sections of the same tumors with monoclonal antibody Ki-67 which identifies all proliferating cells, i.e., the growth fraction. LIs were counted in at least five different areas with high density of labeled cells; at least 1,000 cells were counted. In 13 metastatic tumors, Ki-67 LI was 8.3%-62.6%, and BrdU LI was 5.1%-28.0%. In 18 gliomas, Ki-67 LI was 1.4%-19.3%, and BrdU LI was 0.2%-11.6%. In 7 meningiomas, Ki-67 LI was 0.3%-3.0%, and BrdU LI was 0%-2.0%. Statistical comparison of Ki-67 and BrdU LIs by linear regression analysis revealed a highly significant correlation: BrdU LI = 0.99 + 0.34 Ki-67 LI (r = 0.92, P less than 0.001). A significant heterogeneity of proliferation patterns may occur within one sample from area to area, as well as between different samples of the same tumor, especially in gliomas; thus, some subjective influence on LIs by arbitrary sampling and selection could occur in quantitative evaluation of in situ cell kinetics of human brain tumors. This study indicates that our in vitro BrdU-labeling method allows the in situ identification of S phase cells in excellently preserved fixed tumor tissue which is well suited for further histological examination.(ABSTRACT TRUNCATED AT 250 WORDS)

1H and 13C nuclear magnetic resonance studies of plasma from patients with primary intracranial neoplasms

Plasma from patients with malignant and benign primary intracranial neoplasms and from healthy control subjects has been examined using proton (1H) and carbon-13 nuclear magnetic resonance (NMR) spectroscopy. Some features in the spectra of plasma from patients with malignant tumors differ significantly (p less than 0.01) from the corresponding features in the spectra of plasma from control subjects and from patients with benign tumors. The NMR spectral parameters vary consistently with the Kernohan grade of astrocytoma, which may suggest that they give a measure of tumor growth kinetics. The observed spectral differences are shown to be due to elevated levels of monounsaturated and polyunsaturated fatty acid residues in the plasma of cancer patients. It is proposed that these lipid residues arise from cell membranes shed from cells in growing tumors. The ability to follow tumor growth kinetics directly may be of considerable importance in elucidating the effects of primary intracranial neoplasm therapy.

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.