Cerebral hemisphere astrocytoma: treatment results

Elevated expression of HSP10 protein inhibits apoptosis and associates with poor prognosis of astrocytoma

Astrocytoma is the most common type of primary malignant brain tumor, with pretty lowly 5-year survival rate in patients. Although extended surgical removal of the tumor and postoperative chemotherapy/radiotherapy executed, still there is large recurrence rate, mainly because diffuse glioma tumor cells ubiquitously infiltrate into normal parenchyma. So it becomes a priority to hunt novel molecular and signaling pathway targets to suppress astrocyma progression. HSP10, an important member of Heat shock proteins (Hsps) family, classically works as molecular chaperone folding or degradating of target proteins. Evolutionarily, HSP10 is also reported to be involved in immunomodulation and tumor progression. Poly (ADP-ribose) polymerase (PARP), important in DNA repair, is one of the main cleavage targets of caspase. And cleaved PARP (c-PARP) can serve as a marker of cells undergoing apoptosis. So far, whether the expression of HSP10 or c-PARP is associated with clinicopathologic implication for astrocytoma has not been reported. Meanwhile, it is unclear about the relationship between HSP10 and cell apoptosis. The purpose of this research is to elucidate the association between the expression of HSP10 and c-PARP and clinicopathological characteristics of astrocytoma by immunohistochemistry. The results showed that positive percentage of high HSP10 expression in astrocytoma 42/103, 40.8%) was significantly higher than that in the non-tumor control brain tissues (8/43, 18.6%) (P = 0.01). While no apparent difference of high c-PARP expression existed between astrocytoma and non-tumor control brain tissues. Furthermore, elevated expression of HSP10 was negative related to low expression of c-PARP (r = -0.224, P = 0.023), indicating high expression of HSP10 in astrocytoma inhibited apoptosis process effectively. And overexpression of HSP10 was proved to be the independent poor prognostic factor for astrocytoma by multivariate analysis. Taken together, our results suggest that elevated expression of HSP10 protein inhibits apoptosis and associates with poor prognosis of astrocytoma.

Surgery for malignant gliomas: mechanistic reasoning and slippery statistics

Current surgical treatment of malignant gliomas largely depends on mechanistic reasoning and data collected in non-randomised studies. Technological advance has enabled more accurate resection of tumours and preservation of eloquent brain areas but ethical considerations have restricted randomised trials on the efficacy of surgery to one small trial that found a 3 month survival advantage for patients over age 65 years who received surgery and interim analysis of a larger trial. There is an argument for surgery as a palliative measure in patients with symptoms caused by mechanisms that are surgically remediable. Whether there is any survival advantage from surgery in patients other than those with immediately life-threatening, surgically remediable complications, such as raised intracranial pressure, is unclear. The available data show that if such an advantage does exist, it is modest at best. Adjuvant treatments given surgically are being studied. Chemotherapy wafers are the most prominent of the adjuvant treatments but the evidence available is insufficient to recommend their use in routine practice. In this review we examine the prevailing mechanistic model and observational data; we assess how these are applied and the priorities they indicate for future research.

Proliferative activity and prognosis of low-grade astrocytomas

Well-differentiated astrocytomas may transform into malignant astrocytomas in time. In surgical specimens, when the histological picture strictly corresponds to that of grade II glioma, the transformation is unpredictable. Clinically, the bad outcome of a quota of astrocytomas is a well known phenomenon. The use of proliferation markers, and recently of MIB-1 LI, for detecting the proliferation potential comes out to be a useful tool for prognosis. A survival analysis of fifty astrocytomas grade II according to the WHO classification was performed with univariate and multivariate analysis of a series of clinical and histological parameters. MIB-1 LI was calculated and compared with all the other parameters. A cut-off of 8% of MIB-1 LI divided the astrocytomas in two groups with significantly different survival (p = 0.0066): median survival time of 1062 versus 1686 days. According to multivariate analysis MIB-1 LI resulted to be an independent factor (p = 0.002) along with extension of surgical removal (partial versus total), postoperative Karnofsky status (> or = 70 versus < 70) and age (< or = 30 versus > 30). The interpretation of well-differentiated astrocytomas with high MIB-1 LI is that the increasing number of cycling cells precedes phenotypic transformation. MIB-1 LI can be used as a prognostic factor.

Prognostic factors in low-grade supratentorial astrocytomas: a uni-multivariate statistical analysis in 76 surgically treated adult patients

A retrospective uni-multivariate statistical analysis was performed on 32 prognostic factors to investigate their importance in predicting survival in a series of 76 adult patients with low-grade supratentorial astrocytomas treated over a 13-year period. The end point used for this study was the length of survival. The median survival time was 40 months. Overall actuarial survival at 2, 5, and 10 years was 69%, 38%, and 22%, respectively. Radical resection of the neoformation, a higher preoperative Karnofsky performance status (KPS) score, and an age younger than 50 years are strongly correlated with survival; postoperative radiotherapy appears to be associated with increased survival only in patients under 50 years of age.

Low-grade astrocytomas: prognosis factors and elements of management

BACKGROUND

The literature provides information concerning prognosis of low-grade astrocytomas, but the series are quite heterogeneous in terms of clinical material, neuropathological evaluation, and statistical methods of analysis. Therapeutical indications are poorly defined. The last World Health Organization (WHO) histological classification provided a very precise definition of low-grade gliomas.

METHODS

Taking into account a recent study of our own and literature data, management guidelines of these tumors were proposed.

RESULTS

Grade I (pilocytic and subependymal giant cell astrocytomas) are surgically curable lesions. No adjuvant treatment is mandatory. Management of grade II astrocytomas is less clear-cut. Conservative management is probably possible in young patients without functional threat. The role of surgery on duration of survival has been properly established in very few series and was negative in many others. The role of radiotherapy has been demonstrated in a few subgroups of patients. In our study of ordinary astrocytomas, considering decades of age at diagnosis, survival curve analysis established three prognostic classes of age (before 50, between 50 and 60, and after 60 years of age). Based on our results and on recently published data, a branch decisional approach was proposed for management of grade II astrocytomas. Other grade II gliomas exhibit more favorable prognoses but could be managed in the same manner.

CONCLUSIONS

Ordinary grade II astrocytomas constitute a paradigm of difficult differential management. Further pertinent information on these tumors could come from the field of tumor biology, or be provided by very large and homogeneous groups of patients.

Survival after stereotactic biopsy and irradiation of cerebral nonanaplastic, nonpilocytic astrocytoma

The authors investigated the outcome of stereotactic biopsy and radiotherapy in 35 consecutive adult patients with nonanaplastic, nonpilocytic astrocytomas who were diagnosed between 1982 and 1992. The median patient age at presentation was 32 years. All received fractionated external-beam radiation therapy (median dose 56 Gy) as the initial management strategy. Additional treatment in two patients included intracavitary irradiation with colloidal phosphorus-32. Six patients (17%) had documented tumor progression during the follow-up interval and died. Three others died of causes unrelated to their tumor. Median survival after stereotactic biopsy and irradiation was 118 months (9.8 years). Median survival from the time of onset of neurological symptoms was 148 months (12.3 years). Only three patients required delayed cytoreductive surgery. The outcome of brain astrocytomas, although improved because of earlier diagnosis and therapy, does not substantiate this tumor as having benign behavior; early recognition with neuroimaging, immediate histological diagnosis via stereotactic biopsy, and initial fractionated radiation therapy may provide the potential for longer survival for patients with low-grade astrocytomas. The majority of such surviving patients have a satisfactory quality of life, which is manifested by prolonged normal functional and employment status. The survival data reported in this prospective Phase I-II clinical trial suggest that stereotactic biopsy and radiation therapy are appropriate initial management strategies for astrocytomas.

Radiation therapy with or without surgery in the management of low-grade brain astrocytomas. A retrospective study of 120 patients

From 1977 to 1988, 120 consecutive patients with a diagnosis of low-grade astrocytoma were referred to our department for radiotherapy. Fourty-one patients (group 1) underwent surgery and post operative external radiation therapy (2 gross total resections and 39 subtotal resections). Sixty-nine patients underwent exclusive external radiotherapy (group 2). In ten patients, the irradiation was delivered by stereotactic implantation of iridium-192 wires into the tumor with or without external irradiation (group 3). Ten had pilocytic astrocytomas (mean age, 24 years) and twenty had microcystic astrocytomas (mean age, 35.4 years). The 5- and 10-year survival rates were 55.6% and 44.4%, respectively and 55% and 48%. Ninety astrocytomas were classified as "ordinary" astrocytoma (mean age, 36.8 years). The 5- and 10-year overall survival rates were 51% and 20.5%, respectively. The same probabilities at 5 and 10 years were 65% and 37% respectively, for group 1, 38.8% and 12.7% for group 2 and, 78.8 and 22.5% for group 3. In multivariate analysis, two prognostic factors had a significant impact on overall survival: IK score (IK < 90 vs IK > or = 90, p = 0.0001), surgical resection (surgical resection and post operative radiotherapy vs radiation therapy alone, p = 0.012). However, the patients who underwent surgical resection were those in the best condition, having tumors that were easily accessible and less invasive.

Low grade supratentorial astrocytomas. Management and prognostic factors

BACKGROUND

The authors examined the principal prognostic factors for supratentorial low grade astrocytomas and the effects of treatment on survival time.

METHODS

Fifty-eight patients, 32 males and 26 females, treated from January 1970 through December 1990 are reported. Thirty-five patients underwent surgery, of whom three died. Among the survivors there were 7 gross total resections, 13 subtotal resections, and 12 partial resections. Of the 23 remaining patients, diagnosis was obtained by stereotactic biopsy. Twenty-five patients were irradiated and eight received chemotherapy. The histologic material, originally graded 1 or 2 according to Kernohan's system, was reviewed using the St. Anne-Mayo Clinic system, with which there were 18 Grade 3 tumors.

RESULTS

Six patients had pilocytic astrocytomas (mean age, 18 years), of which three astrocytomas could be removed, and the patients were well 128, 152, and 254 months, respectively, after diagnosis. Among the other three patients, one with a hypothalamic localization refused any form of treatment and died rapidly. The remaining two patients also had deep-seated tumors and were irradiated: one died 17 months later, and the other remained relapse free 56 months after diagnosis. The 49 patients with ordinary astrocytomas who survived surgery (mean age, 37 years) had a median survival time of 64 months and 5- and 10-year survival rates of 54.6% and 34.1%, respectively. Patients with Grade 1 or 2 tumors had a median survival time of 108.6 months, compared with 39.4 months for patients with Grade 3 tumors. Gross total and subtotal resections were significantly associated with longer survival time only in patients with Grade 1 and 2 tumors: in this group, the 5- and 10-year survival rates were 87.5% and 68.2%, respectively, when tumor was completely resected, instead of 57% and 31.2% in patients with incomplete or no surgical resection. There was a trend suggesting that antimitotic drugs and X-ray therapy could benefit patients with Grade 3 tumors.

CONCLUSION

The importance of an accurate histologic grading system and a gross total resection of Grade 1 and 2 astrocytomas is emphasized.

Proliferative potential and prognostic evaluation of low-grade astrocytomas

Despite their histological similarity, low-grade astrocytomas vary widely in their clinical behavior. To elucidate this variable behavior, we measured the proliferative potential of 69 primary and 18 recurrent low-grade astrocytomas and correlated the results with the clinical characteristics and outcome. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR); BUdR-labeled nuclei in excised tumor specimens were identified by immunoperoxidase staining. The BUdR labeling index (LI), or S-phase fraction, ranged from < 1 to 9.3%; the LI was < 1% in 64 (74%) patients and > or = 1% in 23 patients (26%). The LI did not appear to be associated with age, sex, tumor location, or whether the tumor was primary or recurrent. A Cox proportional-hazards analysis of the influence of the LI and other variables (age, sex, tumor location, extent of surgery, primary versus recurrent tumor) on survival showed that the LI and extent of surgery (total resection, subtotal resection, biopsy) were significant in predicting both survival and progression-free survival for all patients and for patients with primary tumors. The LI was also significant in predicting progression-free survival for patients with recurrent tumors. The correlation between the BUdR LI and both survival and time to recurrence suggests that the outcome of low-grade astrocytomas varies according to the proliferative potential. The growth rate of these histologically similar tumors should be assessed individually in order to select specific treatment.

Treatment and survival of low-grade astrocytoma in adults--1977-1988

A retrospective review of the records of the Division of Neuropathology at the New York University Medical Center between 1977 and 1988 revealed 53 cases of adult supratentorial astrocytomas. Fifty were fibrillary, and three were gemistocytic. Two additional patients had pilocytic tumors and were not included in the study. The majority of patients had either a subtotal (64%) or gross total resection (19%). Biopsy (17%) was performed for deep-seated lesions and for those lesions confined to eloquent cortex. Forty-eight patients (91%) received postoperative radiation therapy. The median survival was 7 1/4 years with a 5-year survival of 64%. Multivariate regression analysis demonstrated that the most important prognosticators for improved survival were young age, absence of contrast enhancement of the original tumor on computed tomography (CT) and the performance status of the patient. Patients with hemispheric tumors died from dedifferentiation into an anaplastic astrocytoma or a glioblastoma multiforme, with a median time to recurrence of 4.5 years from the original surgery. Survival from the time of recurrence was 12 months. Subsequent operations confirmed progression towards malignancy in six of seven (86%) recurrent tumors. CT contrast enhancement of the original tumor was associated with a 6.8-fold increase in risk for later recurrence. Patients with thalamic tumors (six patients) had a poor prognosis with a median survival of less than 2 years. A review of their CT scans suggest that four died of progressive low-grade disease; however, confirmatory autopsy data were available for only one patient. This study supports others that have shown improved survival for adult patients with astrocytomas treated in the CT era.

Does the extent of surgery make a difference in high grade malignant astrocytoma?

This paper examines the effect of patient age, tumour grade and extent of surgery on the outcome of treatment of 278 patients with high grade malignant gliomas referred to the Queensland Radium Institute between 1980 and 1987. The aim was to determine whether the extent of surgical resection alters survival rates. The extent of surgery had no effect on survival except for those patients with grade 3 tumours in whom a total excision was possible. Those in whom only a biopsy was done did not have a worse prognosis. Grading was found to be of importance, as patients with grade 3 tumours had a better survival than those with grade 4 tumours. In grade 4 tumours, those under 30 years of age had a better survival than those over 30 years, whereas with grade 3 tumours there was a gradation of age effect (under 40 years best, then 40-49 years, and those 50 years and over doing worst.

Radiation in the treatment of high grade malignant gliomas in Queensland

Two hundred and seventy eight patients with histologically proven grade 3 or grade 4 astrocytomas were referred to the Queensland Radium Institute for consideration of radiotherapy between January 1980 and December 1987. The role of radiation in the management of these tumours was examined with respect to the effects of field size, dose and age. It was found that field size did not have a significant effect on survival; in particular whole brain irradiation for patients with grade 4 tumours was not a significant advantage. The doses used at the Queensland Radium Institute produce similar survivals to those used in other centres. The effect of age was significant. For grade 3 tumours there was a survival advantage to those under 50 years receiving radiation, but not to those above that age. For grade 4 tumours, the survival advantage was for those under 60 years, but those over 60 years did seem to get some benefit although the difference did not reach significance. It is suggested that, as the tumour is generally incurable, these patients may be better served by a short simple palliative course of radiation.

The treatment of low grade cerebral astrocytomas by radiotherapy in Queensland

The records of 108 adult patients with supratentorial low grade astrocytoma presenting between 1/1/80 and 31/12/87 were examined for the following factors which might affect survival: patient age, extent of surgical resection, site of tumour, tumour grade, radiation field size and radiation dose. Univariate analysis showed that patient age, field size and radiation dose were significant prognostic factors, but with multivariate analysis only patient age and radiation field size were significant independent variables. It is possible that field size is a proxy variable for tumour size.

Anaplastic astrocytoma and glioblastoma: pion irradiation with the dynamic conformation technique at the Swiss Institute for Nuclear Research (SIN)

Clinical phase I/II studies have been performed at the Swiss Institute for Nuclear Research (SIN) since February 1982. Fifty-two out of 249 patients accepted for pion treatment by the end of 1986 were treated for malignant glioma with high dose pion irradiation. A substantial influence of their radioresistance was expected from increased radiation quality due to the contribution of high LET particles from pion capture, and by the possibility of target volume shaping and dose distribution related to the dynamic spot-scan conformation technique. The patients' treatment followed a dose escalation program with total doses from 2720-3420 cGy, fraction sizes from 170 to 205 cGy (90% isodose, minimum target dose), and treatment times from 4 to 5 weeks. 12/52 patients received an accelerated treatment with 3280 cGy in 14-22 days. 49/52 patients are eligible: 3 with astrocytoma of clinical aggressive behaviour, 14 with anaplastic astrocytoma (median age 42 years), and 32 patients with glioblastoma (median age 52 years). 8/49 patients had total/subtotal tumour resection, 19 patients a stereotactic biopsy. The patients were divided into three groups according to total dose, and a fourth group which received the accelerated treatment. There was no statistically significant difference in the median survival rate between the four groups, which was 13 months for the non-glioblastoma patients and 9 months for the glioblastoma patients. No radiation necrosis and no demyelination was found in 17 patients (6 recraniotomies, 11 autopsies). In 10/17 patients, clearly identifiable tumour cells were not demonstrated. NMR findings showed the tumour-surrounding oedema mostly stimulated by tumour necrosis and tumour progression. From these findings, further dose escalation programs, together with a shaping of the target volume close to the tumour, are not contraindicated.

Treatment of CNS tumours with conventional radiotherapy: the importance of dose & volume factors in tumour control & CNS radiation tolerance

Improved localisation of central nervous system (CNS) tumours resulting from newer diagnostic imaging techniques may allow the therapeutic irradiation of smaller volumes than currently practiced with the possibility of less normal tissue injury and/or the use of higher radiation doses. The influence of radiation dose and volume on the control rates for various types of CNS tumour and on the radiation tolerance of CNS tissue is imperfectly understood. Available data on these fundamental issues in the radiation treatment of CNS tumours is reviewed.