Neuroinflammation After Stereotactic Radiosurgery-Induced Brain Tumor Disintegration Is Linked to Persistent Cognitive Decline in a Mouse Model of Metastatic Disease

PURPOSE

Improved efficacy of anticancer therapy and a growing pool of survivors give rise to a question about their quality of life and return to premorbid status. Radiation is effective in brain metastasis eradication, although the optimal approach and long-term effects on brain function are largely unknown. We studied the effects of radiosurgery on brain function.

METHODS AND MATERIALS

Adult C57BL/6J mice with or without brain metastases (rat 9L gliosarcoma) were treated with cone beam single-arc stereotactic radiosurgery (SRS; 40 Gy). Tumor growth was monitored using bioluminescence, whereas longitudinal magnetic resonance imaging, behavioral studies, and histologic analysis were performed to evaluate brain response to the treatment for up to 18 months.

RESULTS

Stereotactic radiosurgery (SRS) resulted in 9L metastases eradication within 4 weeks with subsequent long-term survival of all treated animals, whereas all nontreated animals succumbed to the brain tumor. Behavioral impairment, as measured with a recognition memory test, was observed earlier in mice subjected to radiosurgery of tumors (6 weeks) in comparison to SRS of healthy brain tissue (10 weeks). Notably, the deficit resolved by 18 weeks only in mice not bearing a tumor, whereas tumor eradication was complicated by the persistent cognitive deficits. In addition, the results of magnetic resonance imaging were unremarkable in both groups, and histopathology revealed changes. SRS-induced tumor eradication triggered long-lasting and exacerbated neuroinflammatory response. No demyelination, neuronal loss, or hemorrhage was detected in any of the groups.

CONCLUSIONS

Tumor disintegration by SRS leads to exacerbated neuroinflammation and persistent cognitive deficits; therefore, methods aiming at reducing inflammation after tumor eradication or other therapeutic methods should be sought.

Racial/ethnic differences in survival for patients with gliosarcoma: an analysis of the National cancer database

PURPOSE

Gliosarcoma is characterized by the World Health Organization as a Grade IV malignant neoplasm and a variant of glioblastoma. The association of race and ethnicity with survival has been established for numerous CNS malignancies, however, no epidemiological studies have reported these findings for patients with gliosarcoma. The aim of this study was to examine differences by race and ethnicity in overall survival, 30-day mortality, 90-day mortality, and 30-day readmission.

METHODS

Data were obtained by query of the National Cancer Database (NCDB) for years 2004-2014. Patients with gliosarcoma were identified by International Classification of Diseases for Oncology, Third Edition (ICD-O-3)-Oncology morphologic code 9442/3 and topographical codes C71.0-C71.9. Differences in survival by race/ethnicity were examined using univariable and multivariable Cox proportional hazards models. Readmission and mortality outcomes were examined with univariable and multivariable logistic regression.

RESULTS

A total of 1988 patients diagnosed with gliosarcoma were identified (White Non-Hispanic n = 1,682, Black Non-Hispanic n = 165, Asian n = 40, Hispanic n = 101). There were no differences in overall survival, 30- and 90-day mortality, or 30-day readmission between the races and ethnicities examined. Median survival was 10.4 months for White Non-Hispanics (95% CI 9.8, 11.2), 10.2 months for Black Non-Hispanics (95% CI 8.6, 13.1), 9.0 months for Asian Non-Hispanics (95% CI 5.1, 18.2), and 10.6 months for Hispanics (95% CI 8.3,16.2). 7.3% of all patients examined had an unplanned readmission within 30 days.

CONCLUSION

Race/ethnicity are not associated with differences in overall survival, 30-day mortality, 90-day mortality, or 30-day readmission following surgical intervention for gliosarcoma.

Primary and secondary gliosarcomas: clinical, molecular and survival characteristics

Gliosarcoma is classified by the World Health Organization as a variant of glioblastoma. These tumors exhibit biphasic histologic and immunophenotypic features, reflecting both glial and mesenchymal differentiation. Gliosarcomas can be further classified into primary (de novo) tumors, and secondary gliosarcomas, which are diagnosed at recurrence after a diagnosis of glioblastoma. Using a retrospective review, patients seen at MD Anderson Cancer Center between 2004 and 2014 with a pathology-confirmed diagnosis of gliosarcoma were identified. 34 patients with a diagnosis of gliosarcoma seen at the time of initial diagnosis or at recurrence were identified (24 primary gliosarcomas (PGS), 10 secondary gliosarcomas (SGS)). Molecular analysis performed on fourteen patients revealed a high incidence of TP53 mutations and, rarely, EGFR and IDH mutations. Median overall survival (OS) for all patients was 17.5 months from the diagnosis of gliosarcoma, with a progression free survival (PFS) of 6.4 months. Comparing PGS with SGS, the median OS was 24.7 and 8.95 months, respectively (from the time of sarcomatous transformation in the case of SGS). The median OS in SGS patients from the initial diagnosis of GB was 25 months, with a PFS of 10.7 months. Molecular analysis revealed a higher than expected rate of TP53 mutations in GS patients and, typical of primary glioblastoma, IDH mutations were uncommon. Though our data shows improved outcomes for both PGS and SGS when compared to the literature, this is most likely a reflection of selection bias of patients treated on clinical trials at a quaternary center.

An individual patient data meta-analysis on characteristics, treatments and outcomes of glioblastoma/ gliosarcoma patients with metastases outside of the central nervous system

Purpose

To determine the characteristics, treatments and outcomes of patients with glioblastoma multiforme (GBM) or gliosarcoma (GS) and metastases outside of the central nervous system (CNS).

Methods

PubMed and Web of Science searches for peer-reviewed articles pertaining to GBM/ GS patients with metastatic dissemination were conducted using the keywords gliosarcoma, glioblastoma, GBM, metastasis, metastases and metastatic. Additionally, we performed hand search following the references from the selected papers. Cases with metastases to the CNS were excluded and evaluated in a separate study.

Results

109 articles published between 1928 and 2013 were eligible. They reported on 150 patients. We observed a remarkable increase in the number of cases per decade over time. Median overall survival from diagnosis of metastasis (OS_M+) was 6.0 ± 0.8 months and median overall survival from initial diagnosis (OS_ID) 13 ± 2.4 months. On univariate analyses, gender, age, the histological subtype, the time interval between initial diagnosis and diagnosis of metastasis and pulmonary involvement did not influence OS_M+. We did not observe any substantial treatment progress. A comparison of the present cohort with 84 GBM/ GS patients with exclusive CNS dissemination suggests that metastases outside the CNS are related to a slightly more favorable outcome.

Conclusions

The occurrence of extra-CNS metastasis from GBM/ GS is associated with a dismal prognosis, however it seems to compare slightly favorable to CNS dissemination. Crucial treatment progress has not been achieved over recent decades. A central registry should be considered to consecutively gain more information about the ideal therapeutic approach.

Clinical characteristics and outcomes for a modern series of primary gliosarcoma patients

BACKGROUND

Primary gliosarcoma (PGS) is a rare central nervous system tumor with limited experience reported in the literature. In the current study, the authors present a modern series of confirmed PGS cases treated in the era of magnetic resonance imaging (MRI), after the accepted glioblastoma management of resection, radiation, and temozolomide.

METHODS

Using a retrospective review, patients with confirmed PGS were identified (1996-2008). Cases were determined to be PGS by central pathology review using the 2007 World Health Organization criteria. Extensive chart review was performed to gather clinical and pathologic data on these cases.

RESULTS

All but 1 patient had undergone a preoperative MRI, with 1 patient receiving a computed tomography scan due to a cardiac pacemaker. A total of 10 patients received radiotherapy with concurrent and adjuvant temozolomide chemotherapy, and 8 patients received radiotherapy alone or in combination with other chemotherapeutic agents. In 2 patients, the history of adjuvant treatment could not be confirmed. The overall median survival was 13.9 months (range, 2.2-22.9 months). Patients with gliosarcomas resembling meningioma were found to have a significantly prolonged median survival compared with patients harboring gliosarcoma resembling glioblastoma multiforme (16 months vs 9.6 months; P = .011). However, no difference in survival was noted between patients who received concurrent radiotherapy and temozolomide compared with those who did not (10.4 months vs 13.9 months; P = .946).

CONCLUSIONS

The results of the current study support previous hypotheses that there are 2 distinct types of PGS. The type mimicking the appearance of a meningioma appears to carry a significantly more favorable prognosis, most likely due to an increased chance at achieving macroscopic total resection.

[Cerebral gliosarcoma: clinico-pathologic study of 8 cases]

BACKGROUND

Gliosarcomas are biphasic neoplasms composed of a glioblastoma admixed to a sarcomatous component with different lines of differentiation. Histogenesis of these tumors is still discussed.

AIM

Our objective is to specify clinical and pathological characteristics of this rare neoplasm and to discuss its histogenesis.

METHODS

Retrospective study of eight cases of gliosarcomas diagnosed between January 1998 and December 2004. Clinical, radiological, therapeutic and follow-up data were reviewed. Histological features and immunohistochemical results were also included in this review.

RESULTS

Five patients were male, three women with a median age of 50.7 (range 31-74 years). Symptoms were dominated by intracranial hypertension and paralysis. The most common location was parietal or temporo-parietal (5 cases: 62.5%). Pathological exam including histochemical and immunohistochemical study confirmed the diagnosis of gliosarcoma in all cases. Sarcomatous component had features of fibrosarcoma in 5 cases, osteosarcoma in 2 cases and malignant fibrous histiocytoma in 1 case. All patients were treated by surgical excision (complete in five cases and partial in three cases). Adjuvant radiotherapy was received in three cases. One patient was lost on follow-up. Two patients died from postoperative. complications and the five remaining patients died with a medium follow up of 9 months (extremes: 2-24 months).

CONCLUSION

Clinical, radiological and follow-up features of gliosarcomas share great similarities with glioblastomas. Histopathological, histochemical and immunohistochemical studies are helpful in accuracy diagnosis. Recent cytogenetic and molecular data support a monoclonal origin for these tumors.

Detrimental effects of tumor progression on cognitive function of patients with high-grade glioma

PURPOSE

There is growing recognition that the primary cause of cognitive deficits in adult patients with primary brain tumors is the tumor itself and more significantly, tumor progression. To assess the cognitive performance of high-grade glioma patients, prospectively collected cognitive performance data were analyzed.

PATIENTS AND METHODS

We studied 1,244 high-grade brain tumor patients entered onto eight consecutive North Central Cancer Treatment Group treatment trials that used radiation and nitrosourea-based chemotherapy. Imaging studies and Folstein Mini-Mental State Examination (MMSE) scores recorded at baseline, 6, 12, 18, and 24 months were analyzed to assess tumor status and cognitive function over time.

RESULTS

The proportion of patients without tumor progression who experienced clinically significant cognitive deterioration compared with baseline was stable at 6, 12, 18, and 24 months (18%, 16%, 14%, and 13%, respectively). In patients without radiographic evidence of progression, clinically significant deterioration in MMSE scores was a strong predictor of a more rapid time to tumor progression and death. At evaluations preceding interval radiographic evidence of progression, there was significant deterioration in MMSE scores for patients who were to experience progression, whereas the scores remained stable for the patients who did not have tumor progression.

CONCLUSION

The proportion of high-grade glioma patients with cognitive deterioration over time is stable, most consistent with the constant pressure of tumor progression over time. Although other factors may contribute to cognitive decline, the predominant cause of cognitive decline seems to be subclinical tumor progression that precedes radiographic changes.

Safety and efficacy of convection-enhanced delivery of ACNU, a hydrophilic nitrosourea, in intracranial brain tumor models

Convection-enhanced delivery (CED) is a local infusion technique, which delivers chemotherapeutic agents directly to the central nervous system, circumventing the blood-brain barrier and reducing systemic side effects. CED distribution is significantly increased if the infusate is hydrophilic. This study evaluated the safety and efficacy of CED of nimustine hydrochloride: 3-[(4-amino-2-methyl-5-pyrimidinyl) methyl]-1-(2-chloroethyl)-1-nitrosourea hydrochloride (ACNU), a hydrophilic nitrosourea, in rat 9 L: brain tumor models. The local neurotoxicity of ACNU delivered via CED was examined in normal rat brains, and the maximum tolerated dose (MTD) was estimated at 0.02 mg/rat. CED of ACNU at the MTD produced significantly longer survival time than systemic administration (P < 0.05, log-rank test). Long-term survival (80 days) and eradication of the tumor occurred only in the CED-treated rats. The tissue concentration of ACNU was measured by high-performance liquid chromatography, which revealed that CED of ACNU at the dose of 100-fold less total drug than intravenous injection carried almost equivalent concentrations of ACNU into rat brain tissue. CED of hydrophilic ACNU is a promising strategy for treating brain tumors.

TGF-beta2 inhibition augments the effect of tumor vaccine and improves the survival of animals with pre-established brain tumors

TGF-beta2 secretion by high grade gliomas has been implicated as one of the major factors contributing to tumor growth, alterations in the host immune response to tumor, and failure of gliomas to respond to current immunotherapy strategies. We hypothesized that targeted delivery and inhibition of TGF-beta2 by TGF-beta2 antisense oligonucleotides (AS-ODNs) would overcome tumor-induced immunosuppression and enhance the capacity of tumor vaccines to eradicate established brain tumors. Utilizing the mRNA sequences of TGF-beta2, specific AS-ODNs were constructed and tested for their ability to inhibit TGF-beta2 production in 9L glioma cells. The effect of combining local intracranial administration of antisense ODNs with systemic tumor vaccine was examined. Fisher 344 rats were vaccinated subcutaneously with irradiated 9L tumor cells 3 days after intracranial tumor implantation. Four days after vaccination, ODNs were administered into the tumor mass and survival was followed. ODNs delivered locally distributed widely within the brain tumor mass and inhibited TGF-beta2 expression. Survival of tumor-bearing rats treated with the combination of local antisense and systemic tumor vaccine was significantly enhanced (mean survival time (MST): 48.0 days). In contrast, MST for animals treated with nonsense plus vaccine, vaccine alone, antisense alone or PBS showed no survival advantage and no statistical differences between groups (33.5 days, 29.0 days, 37.5 days, and 31.5 days, respectively). Our data supports the hypothesis that local administration of antisense TGF-beta2 ODNs combined with systemic vaccination can increase efficacy of immunotherapy and is a novel, potentially clinically applicable, strategy for high-grade glioma treatment.

Gliosarcomas: analysis of 11 cases do two subtypes exist?

There are conflicting reports regarding gliosarcomas. The goal of this study is to examine clinical, radiological, surgical and therapeutic aspects of 11 patients with gliosarcoma. Between 1993 and 2001, 11 patients with cerebral gliosarcoma were treated at our Institute. Ten patients underwent surgery and one patient had stereotactic biopsy. Four patients received whole brain radiotherapy with (60)Co, five underwent radiotherapy with LINAC extended 2 cm beyond the edema margins. One patient refused any additional treatment after surgery and one patient was not treated postoperatively for poor clinical conditions (KPS 40). Chemotherapy (temozolomide) was administered to four patients. Four patients had a prevalence of sarcomatous component that corresponded to surgical and radiological aspects similar to meningioma while six patients showed a prevalence of gliomatous component and radiological and surgical aspects similar to those of glioblastomas. Surgical resection was total in six and subtotal in four patients. Patients with prevalent sarcomatous component showed median survival time more prolonged than patients with prevalent gliomatous component (71 +/- 6 weeks vs. 63 +/- 6; P=0.0417). Moreover, the survival rate differed in relation to the therapy: patients treated with multimodality therapy (surgery, radiotherapy and chemotherapy) had a longer survival time than patients treated in single or bimodality. Despite prognosis of gliosarcomas remains poor, a multidisciplinary approach (surgery, radiotherapy and chemotherapy) seems to be associated with slight more prolonged survival times.

Local Delivery of Interleukin-2 and Adriamycin is Synergistic in the Treatment of Experimental Malignant Glioma

INTRODUCTION

Local delivery of adriamycin (ADR) via biodegradable polymers has been shown to improve survival in rats challenged intracranially with 9L gliosarcoma. Likewise, local delivery of interleukin-2 (IL-2) has been shown to extend survival in experimental brain tumor models. In the current study, we hypothesized that local delivery of ADR and IL-2 might act synergistically against experimental intracranial glioma.

METHODS

Polyanhydride polymers (PCPP-SA) containing 5% ADR by weight were prepared using the mix-melt method. IL-2 polymer microspheres (IL-2 MS) were produced via the complex coacervation of gelatin and chondroitin sulfate in the presence of IL-2. Sixty male Fisher 344 rats received an intracranial challenge with a lethal dose of 9L gliosarcoma cells. In addition, a group of rats were injected with either IL-2 MS or empty microspheres. Five days later they received ADR or blank polymer. There were a total of four treatment groups: (1) empty microspheres, blank polymer; (2) empty microspheres, ADR polymer; (3) IL-2 MS, blank polymer; and (4) IL-2 MS, ADR polymer.

RESULTS

Compared to control animals treated with empty microspheres and blank polymer, animals receiving empty microspheres and ADR polymer (P < 0.0004), IL-2 MS and blank polymer (P < 0.0005), and IL-2 MS combined with ADR polymer (P < 0.0000002) all showed statistically significant improvement in survival. In addition, animals receiving the IL-2/ADR combination had significantly extended survival compared to either ADR or IL-2 alone (P < 0.000003 and P < 0.0004, respectively).

CONCLUSIONS

Both ADR and IL-2, when delivered locally, are effective monotherapeutic agents against experimental intracranial gliosarcoma. The combination ADR and IL-2 therapy is more effective than either agent alone.

Local delivery of minocycline and systemic BCNU have synergistic activity in the treatment of intracranial glioma

Minocycline, a tetracycline derivative, has been shown to inhibit tumor angiogenesis through inhibitory effects on matrix metalloproteinases. Previous studies have shown this agent to be effective against a rodent brain tumor model when delivered intracranially and to potentiate the efficacy of standard chemotherapeutic agents. In the present study, the in vivo efficacy of intracranial minocycline delivered by a biodegradable controlled-release polymer against rat intracranial 9L gliosarcoma was investigated to determine whether it potentiates the effects of systemic 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU). Minocycline was incorporated into the biodegradable polymer polyanhydride poly[bis(p-carboxyphenoxy)propane-sebacic acid] (pCPP:SA) at a ratio of 50:50 by weight. The release kinetics of minocycline from the polymer were assessed. For the efficacy studies, female Fischer 344 rats were implanted with 9L glioma. Treatment with minocycline delivered by the pCPP:SA polymer at the time of tumor implantation resulted in 100% survival in contrast to untreated control animals that died within 21 days. Treatment with the minocycline-polymer 5 days after tumor implantation provided only modest increases in survival. The combination of intracranial minocycline and systemic BCNU extended median survival by 82% compared to BCNU alone (p < 0.0001) and 200% compared to no treatment (p < 0.004). We conclude that local intracranial delivery of minocycline from biodegradable controlled-release polymers inhibits tumor growth and may have clinical utility when combined with a chemotherapeutic agent.

Radiotherapy in Supratentorial Gliomas

PURPOSE

Analysis of the results of radiotherapy in a large group of cerebral gliomas with identification of prognostic factors and the outcome with respect to different decades of treatment.

PATIENTS AND METHODS

Two decades (1979-1999) of radiotherapy in supratentorial astrocytic and oligodendroglial tumors (n = 821) at the University Hospital Groningen were retrospectively evaluated. Prognostic factors for survival were analyzed. Two decades of radiotherapy treatment were compared with respect to radiotherapy dose and treatment-field design.

RESULTS

Glioblastoma multiforme, including gliosarcoma, was the most frequent supratentorial glioma (n = 442) with a poor survival, i.e., median survival time (MST) 7 months, especially in patients > 50 years of age and with poor performance. Patients with good performance were selected for radiotherapy with an optimum dose of 60 Gy local-field irradiation. However, in patients with poor prognosis, no radiotherapy was applied or a shorter treatment scheme was given. Anaplastic astrocytomas (n = 131) were treated in the same way as glioblastoma multiforme. Over time, a decrease in radiation dose (from 60 to 45 Gy) and from whole brain irradiation to local-field treatment was observed, following the literature. In low-grade gliomas, prognostic factors for survival were age, performance, and extent of resection. Gemistocytic astrocytoma (n = 15) had an inferior survival compared to astrocytoma (MST 46 vs. 54 months), but a superior survival compared to anaplastic astrocytoma (MST 10 months). The presence of an oligodendroglial component in a glioma implied a superior survival compared to the astrocytic gliomas. The inherent biology of the glioma is reflected by the study of recurrent tumors with progression to higher grades of malignancy in 32-40% and by the histology of recurrent oligodendroglial tumors. In comparing two decades of radiotherapy in gliomas, no differences in survival were observed despite the technological improvements. However, reduction in long-term side effects was not evaluated, especially in low-grade gliomas which were treated in the second decade of the study with local fields only and a reduced radiotherapy dose using computerized three-dimensional (3-D) planning.

CONCLUSION

Radiotherapy does not cure cerebral glioma. Prognostic factors for survival are histopathologic classification and grading, age, and patient performance. Technological improvements do not improve survival, but possibly reduce late effects.

Sustained release of low-dose ganciclovir from a silicone formulation prolonged the survival of rats with gliosarcomas under herpes simplex virus thymidine kinase suicide gene therapy

A silicone formulation of ganciclovir (GCV-pellet) was developed to enhance the cytotoxic effects of herpes simplex virus thymidine kinase suicide gene therapy. The effectiveness of this drug delivery system was assessed in a rat 9L gliosarcoma model. The GCV-pellets (1 mm in length and in diameter) used in this experiment contained a total amount of 0.15 mg of GCV. In vitro experiments demonstrated that GCV was gradually released over a period of 7 days. Five days after stereotactic tumor inoculation into the right caudate nucleus, a herpes simplex virus type 1 (HSV-1) vector expressing herpes simplex virus thymidine kinase (HSV-tk) (T1, 2x10(6) pfu) was administered at the same location. The survival rate of the group treated with the GCV-pellet was compared with that of the T1 group injected intraperitoneally (IP) with GCV (30 mg/kg/day for 7 days). The GCV-pellet-treated group had a significantly prolonged survival (a median of more than 80 days) compared with the GCV IP group (a median of 65 days) and with control groups (P<0.05). The control groups (untreated or receiving only the virus vector) had a survival of 35-38 days. The survival rate of the GCV-pellet group over 80 days was 75%, and all the rats that survived more than 80 days and did not show tumors upon histological examination of the brain were deemed cured. No toxic effects or immunological reactions were observed histologically around the pellet in brain sections from the rats treated with the GCV-pellet. After GCV-pellet inoculation into the tumor, drug concentrations were kept at 1-10 microg/g tissue for 3-4 days. When the same dose of GCV (0.15 mg) in aqueous solution was injected into the tumor, GCV concentrations reached a peak of 0.5 mg/g tissue after 30 min and decreased below measurable level within 12 h. After IP injections of 3 mg GCV, GCV concentrations in the tumor reached a peak of 5.7 microg/g tissue after 30 min and also decreased below measurable level within 12 h. This sustained release of a low and effective GCV dose with the silicone formulation significantly prolonged survival in combinations with HSV-tk expression if compared to IP administration of GCV. Histological examination suggests that the treatment appears to be safe.

Safety of thrice-daily hyperfractionated radiation and BCNU for high-grade gliomas

PURPOSE

To investigate the safety of thrice-daily hyperfractionated radiotherapy (RT) given in conjunction with BCNU (carmustine) in high-grade gliomas.

METHODS AND MATERIALS

Patients >18 years old with newly diagnosed high-grade gliomas were eligible. The dose of radiation was 5040 cGy, with a 1440-cGy boost in 180 cGy fractions delivered thrice daily in two 6-day periods with a 2-week interval. BCNU (200 mg/m(2)) was administered on the first day of radiation, then every 7 weeks for 1 year and every 10 weeks for another year.

RESULTS

Eighteen patients were enrolled. The mean age was 49.6 years. Sixteen patients had astrocytomas (Grade 3 or 4 in 5 and 11 patients, respectively) and 2 had oligoastrocytomas (Grade 3 and 4 in 1 patient each). One underwent total resection, 9 subtotal resection, and 8 biopsy only. Thirteen patients had stable disease, 4 regression, and 1 progression. The median time to progression was 37.8 weeks. The median overall survival was 44.4 weeks. Nine patients had neurologic toxicities, including 2 deaths at 69 and 139 weeks.

CONCLUSION

This regimen is unacceptably toxic. Factors that could have contributed to the toxicity may include the total radiation dose, thrice-daily hyperfractionation, and the concurrent use of i.v. BCNU.

Gliosarcoma: a clinical study

BACKGROUND AND PURPOSE

Gliosarcomas are rare biphasic neoplasms of the central nervous system composed of a glioblastoma multiforme (GBM) admixed with a sarcomatous component. There are conflicting reports regarding their clinical aggressiveness. Four hundred and twenty-two consecutive patients with GBM were treated at our hospital between 1980 and 1999, among them 12 gliosarcomas. The goal of this study was to examine clinical features, treatment, survival and patterns of failure of gliosarcoma patients and to compare them with the entire group of GBM patients. This comparison was refined by a matched pair analysis with a group of 12 GBM patients selected for age, Karnofsky performance status, resection status, fractionation scheme and total dose (control GBM group).

MATERIALS AND METHODS

Seven gliosarcoma patients were male, five female, with a median age of 56 years (range 37-76 years). The median tumor size was 4.5 cm (range 3-8 cm). The locations, all supratentorial, included temporal in six, parietal in five, frontal in four and occipital in one patient. All patients underwent tumor resection followed by postoperative radiation therapy.

RESULTS

Median survival was 11.5 months for the gliosarcoma group, 8.1 months for the entire GBM group (log rank test, P=0.16) and 11.0 months for the control GBM group (log rank test, P=0.36). All gliosarcoma patients had local tumor recurrences and died due to neurologic causes within 19.3 months after radiation therapy.

CONCLUSIONS

With regard to clinical features, survival and patterns of failure, gliosarcomas and GBM cannot be distinguished clinically. Therefore, the same principles should be applied for the treatment of these tumors.

Boron neutron capture therapy: effects of split dose and overall treatment time

New clinical protocols are being developed that will entail the administration of considerably higher doses of the boron delivery agent boronophenylalanine (BPA) than those in current clinical use. Fractionation (2 or 4 fractions) of BPA mediated boron neutron capture therapy (BNCT) is also under consideration at some clinical centres. Given the considerably higher infusion volumes that will be entailed in the delivery of BPA in the new high dosage protocols, there will be a requirement to extend the gap between fractions to 2 or more days. In order to assess the effects of a 2 fraction protocol on the therapeutic efficacy of BPA mediated BNCT, a series of split dose irradiations (two equal fractions) were undertaken using the rat intracranially implanted 9L gliosarcoma model. A single dose exposure to BPA mediated BNCT of 3.0 Gy resulted in long term survival levels of 50%. Survival levels increased to 71% and 77% with a 3 and 5 day gap between dose fractions (two equal fractions), respectively, using the same total dose. A further increase in the time interval between dose fractions to 7 days resulted in a reduction in survival to 36%. However, there was no significant difference between the single dose and the 3, 5 and 7 day survival data (P > 0.1) The difference between the 5 and 7 day split dose survival data was of border-line significance (P = 0.05). It is anticipated that mucositis, could become a potential problem in future BNCT clinical protocols involving higher doses, larger field sizes or multiple fields. The potential sparing of the oral mucosa, due to repopulation during the interval between the two fractions, was investigated using a series of split dose BPA mediated BNC irradiations. The ventral surface of the rat tongue was utilised as a model for oral mucosa. The ED50 (50% incidence) values for the ulceration end point were 3.0+/-0.1, 3.2+/-0.1, 3.0+/-0.1 and 3.6+/-0.1 Gy, for 3, 5, 7 and 9 day splits between doses, respectively. It is evident from this data that there were no significant changes in the ED50 (p < 0.001) until the 9 day dose split, when the ED50 value was 20% higher than the ED50 value after a 7 day split. It was concluded that the two fraction BNCT protocol, with dose splits of up to 5 days, did not diminish the therapeutic response of the rat 9L gliosarcoma, when compared with a single dose BNCT protocol. Tolerance of the oral mucosa to BNC irradiation was not increased until there was a 9 day gap between fractions. However, the beneficial effects of dose sparing at this time interval between doses, would probably be counteracted by a reduction in the therapeutic effectiveness of the BNCT modality, due to repopulation of tumour clonogens between doses.

A phase II study of temozolomide vs. procarbazine in patients with glioblastoma multiforme at first relapse

A randomized, multicentre, open-label, phase II study compared temozolomide (TMZ), an oral second-generation alkylating agent, and procarbazine (PCB) in 225 patients with glioblastoma multiforme at first relapse. Primary objectives were to determine progression-free survival (PFS) at 6 months and safety for TMZ and PCB in adult patients who failed conventional treatment. Secondary objectives were to assess overall survival and health-related quality of life (HRQL). TMZ was given orally at 200 mg/m(2)/day or 150 mg/m(2)/day (prior chemotherapy) for 5 days, repeated every 28 days. PCB was given orally at 150 mg/m(2)/day or 125 mg/m(2)/day (prior chemotherapy) for 28 days, repeated every 56 days. HRQL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30 [+3]) and the Brain Cancer Module 20 (BCM20). The 6-month PFS rate for patients who received TMZ was 21%, which met the protocol objective. The 6-month PFS rate for those who received PCB was 8% (P = 0.008, for the comparison). Overall PFS significantly improved with TMZ, with a median PFS of 12.4 weeks in the TMZ group and 8.32 weeks in the PCB group (P = 0.0063). The 6-month overall survival rate for TMZ patients was 60% vs. 44% for PCB patients (P = 0.019). Freedom from disease progression was associated with maintenance of HRQL, regardless of treatment received. TMZ had an acceptable safety profile; most adverse events were mild or moderate in severity.

An alternative method to stereotactic inoculation of transplantable brain tumours in large numbers of rats

The rat 9L gliosarcoma brain tumour model has been widely used in brain cancer studies. Intracerebral implantation of the cells in the parietal lobe of the brain has been performed using the stereotactic or freehand inoculation methods. For large numbers of rats, we wished to develop a method more accurate and precise than the freehand method, but less labour intensive than the stereotactic method. A template implantation technique was developed and compared quantitatively with the stereotactic method. Rats were inoculated with either the template or stereotactic method at doses of 1000, 5000, 10000, 20000 or 40000 cells. Results of this comparison showed that the template method is precise and accurate for tumour placement within the brain cortex, and decreases labour requirements. Mean survival rates between groups were not significantly different at doses of 5000, 20000 or 40000 cells inoculated. Significance was seen at the low dose of 1000 cells (P < 0.001). This was attributable to an absence of tumour growth in five of six stereotactic rats in this group. Significance was also seen at the 10000 dose level (P < 0.05) with the stereotactic rats again surviving longer than the template rats. However, in this case all the stereotactic rats had tumour growth. Brain weights did not differ significantly between groups, except at the 1000 dose level where no growth of tumour occurred in five of the six stereotactic animals. Body weight gain within one week following surgery did not differ significantly between any of the groups at alpha = 0.05. Studies on rat cadavers showed no statistical difference in placement measurements between the stereotactic and template methods. These results indicate that the template method for intracerebrally implanting tumour cells in rats provides a precise, accurate and rapid procedure that maximizes reproducibility with a significant reduction in labour requirements, when compared with the conventional stereotactic methodology.

Increased tumor cures using combined radiosurgery and BCNU in the treatment of 9l glioma in the rat brain

PURPOSE

Radiosurgery refers to the delivery of high, single focused beams of ionizing radiation to defined intracranial lesions. 1,3 Bis[2-chloroethyl]-1-nitrosourea (BCNU) and cis-diammine-1, 1-cyclobutane-dicarboxylate platinum (II) (carboplatin) are commonly used cytotoxic agents for the treatment of malignant gliomas of the brain. Drug therapies have exhibited a modest enhanced cell killing when combined with radiation in experimental animal tumor systems. The purpose of the present study was to investigate the role of cytotoxic drugs, such as BCNU and carboplatin, in combination with a single high dose of radiosurgery on the tumor control rates of 9L tumors in the rat brain.

METHODS AND MATERIALS

Combined radiosurgery (25 Gy single dose) and/or chemotherapy (a single dose of BCNU, 7 mg/kg, i.p. 1.5 or 16 h prior to or 16 h after irradiation or a single dose of carboplatin, 30 mg/kg, administered either 1 h or 4 h prior to irradiation) was delivered 12 days after stereotactic tumor implantation. For dose escalation study, 4-10 mg/kg of BCNU was used.

RESULTS

The radiation alone group showed a dose-dependent survival. A single dose of 25 Gy to the control group resulted in an increase of the median survival time from 20 days to 42 days, but all animals died of the tumor in 50 days. A significant prolongation of the median survival time of animals was more than 100 days, resulting in animal cures of 50% or more when combined with radiosurgery (25 Gy) and BCNU (7 mg/kg). BCNU alone did not prolong the median survival time of the animal with the 9L brain tumor. In contrast, there was no survival improvement when the animals were treated with combined radiosurgery and carboplatin. None of the long-term surviving animals showed any significant brain tissue damage as evaluated by histopathology and clinical observations.

CONCLUSION

The data clearly suggest that the combined modalities of radiosurgery and concomitant BCNU represent an effective therapeutic regimen in the treatment of radioresistant human malignant gliomas of the brain. This study represents the first experimental report of the effectiveness of combined chemotherapy and radiosurgery.

Phase I study of adenoviral delivery of the HSV-tk gene and ganciclovir administration in patients with current malignant brain tumors

Between December 1996 and September 1998, 13 patients with advanced recurrent malignant brain tumors (9 with glioblastoma multiforme, 1 with gliosarcoma, and 3 with anaplastic astrocytoma) were treated with a single intratumoral injection of 2 x 10(9), 2 x 10(10), 2 x 10(11), or 2 x 10(12) vector particles (VP) of a replication-defective adenoviral vector bearing the herpes simplex virus thymidine kinase gene driven by the Rous sarcoma virus promoter (Adv.RSVtk), followed by ganciclovir (GCV) treatment. The VP to infectious unit ratio was 20:1. Our primary objective was to determine the safety of this treatment. Injection of Adv.RSVtk in doses <==2 x 10(11) VP, followed by GCV, was safely tolerated. Patients treated with the highest dose, 2 x 10(12) VP, exhibited central nervous system toxicity with confusion, hyponatremia, and seizures. One patient is living and stable 29.2 months after treatment. Two patients survived >25 months before succumbing to tumor progression. Ten patients died within 10 months of treatment, 9 from tumor progression and 1 with sepsis and endocarditis. Neuropathologic examination of postmortem tissue demonstrated cavitation at the injection site, intratumoral foci of coagulative necrosis, and variable infiltration of the residual tumor with macrophages and lymphocytes.

Neuropathology of ablation of rat gliosarcomas and contiguous brain tissues using a microplanar beam of synchrotron-wiggler-generated X rays

Adult-rat-brain tissues display an unusually high resistance to necrosis when serially irradiated with parallel, thin slices of a microplanar (i.e., microscopically thin and macroscopically broad) beam of synchrotron-wiggler-generated, approx. 35-120 keV (median approx. 50 keV) Gd-filtered X rays at skin-entrance absorbed doses of 312 to 5000 Gy per slice. Such microplanar beams were used to irradiate young adult rats bearing right frontocerebral 9L gliosarcomas (approx. 4 mm diameter), through a volume of tissue containing the tumor and contiguous brain tissue, either in a single array or in 2 orthogonally crossed arrays of tissue slices. Each array included 101 parallel microplanar slices, 100 microm center-to-center distance, each slice being approx. 25 microm wide and 12 mm high, with skin-entrance absorbed doses of 312.5 Gy or 625 Gy per slice. Compared with unirradiated controls with a median survival time of 20 days after tumor initiation, the median survival time was extended in irradiated rats by 139 days (625 Gy, crossed arrays), 96 days (312 Gy, crossed arrays) or 24 days (625 Gy, single array). The tumors disappeared in 22 of the 36 irradiated rats, 4/11 even after unidirectional microbeam irradiation. The extent and severity of radiation damage to the normal brain in rats with or without tumor was graded histopathologically. Correlation of those grades with radiation doses shows that loss of tissue structure was confined to beam-crossing regions and that only minor damage was done to zones of the brain irradiated unidirectionally.

Gliosarcoma. A study of 13 tumors, including p53 and CD34 immunohistochemistry

OBJECTIVE

Gliosarcoma is a biphasic neoplasm composed of a glioblastoma multiforme admixed with a sarcomatous component that is presumed to arise from a malignant transformation of the hyperplastic vasculature elements. We studied 13 cases of gliosarcoma to describe the clinical and pathologic features of this tumor. In addition, immunohistochemical analysis using p53 and CD34 was performed in an attempt to examine the histogenesis of gliosarcomas.

DESIGN AND SETTING

A retrospective study of 13 patients with gliosarcoma from a tertiary care center.

RESULTS

The 13 patients (7 women, 6 men) had a median age of 62 years (range, 33 to 79 years). All patients were initially treated with surgical excision followed by adjuvant radiation therapy, and two received adjuvant chemotherapy. Nine patients died of disease (median, 9 months; range, 1 to 17 months). Three patients were alive with evidence of residual tumor at most recent follow-up (median, 18 months; range, 6 to 41 months). A single patient was lost to follow-up. Histologically, all neoplasms consisted of an admixture of glioblastoma multiforme and sarcomatous elements. The sarcomatous component resembled fibrosarcoma in 12 cases and a malignant fibrous histiocytoma in one case. The sarcoma appeared to arise from hyperplastic vasculature in five tumors. CD34 staining in all five of these cases was negative. Immunostaining for p53 was observed in eight tumors (61.5%). p53 positivity was definitely present in both glial and sarcomatous components in all but three positive cases. The degree of staining was comparable between the two elements in five cases, present in only the glial component in two cases, and not able to be reliably assigned to one or the other component in one case.

CONCLUSION

Gliosarcoma is an aggressive-behaving neoplasm, as previously reported. The presence of p53-positive immunostaining, similar to glioblastoma multiforme, may be indicative of a role for the p53 gene in these neoplasms. A lack of CD34 staining does not support an endothelial cell origin for gliosarcoma.

Cerebral gliosarcoma: prognostic factors

The authors report their results in a retrospective study of 6 cases of gliosarcoma. In 3 cases gliosarcoma presented features similar to those of glioblastoma, both at CT scan and macroscopically; in the other 3 cases they resembled meningioma. Average survival varied considerably and was correlatable to the CT features of the lesion (14 months for glioblastoma, 7 for meningioma). It seems likely that patients who have gliosarcoma with CT features suggestive of meningioma may have prolonged survival.

Clinicopathologic features of primary and postirradiation cerebral gliosarcoma

BACKGROUND

Gliosarcoma is an uncommon malignant brain tumor with mixed glial and mesenchymal elements. Experience is limited to case series, and pathologic data are disparate, leading to uncertainty about clinical features, management, and histogenesis.

METHODS

A clinicopathologic review of 32 patients with survival analysis and immunohistochemical studies was performed including glial fibrillary acidic protein analysis, alpha-1-antitrypsin (alpha-1-AT) analysis, and smooth muscle actin (SMA) analysis.

RESULTS

Twenty-five patients had primary gliosarcoma, whereas 7 developed gliosarcoma after irradiation for glioblastoma multiforme (GBM). Clinical features were similar to those of GBM. Most tumors were intraaxial and diffusely infiltrating by radiologic studies and at surgery. Median survival for primary gliosarcoma was 25 weeks overall, with patients who received irradiation surviving longer (46 vs. 13 weeks, P < 0.025). Gliosarcoma occurring after irradiation appeared hyperdense by computed tomography in five of seven cases, and median survival was 53 weeks. Primary gliosarcoma was a dimorphic tumor with malignant glial elements and features of malignant fibrous histiocytoma (MFH) or fibrosarcoma and one osteosarcoma. Smooth muscle actin labeled tumor vessels heavily, but in 15/25 primary cases, it extended to the surrounding spindle cells. The remaining cases appeared morphologically like MFH and tended to be positive for alpha-1-AT. Postirradiation gliosarcoma was fibrosarcomatous with positive SMA in 75% of the cases examined.

CONCLUSIONS

Gliosarcoma behaves clinically like GBM, and survival may be improved by cranial irradiation of selected patients. Smooth muscle actin reactivity in sarcomatous areas suggests histogenesis in some tumors from the smooth muscle within GBM, whereas others may arise via different mechanisms including differentiation from a pluripotential precursor. Transformation of the smooth muscle within GBM may have therapeutic implications for antiangiogenesis agents.

Influence of an anti-angiogenic treatment on 9L gliosarcoma: oxygenation and response to cytotoxic therapy

Tissue oxygen tensions were measured in subcutaneously growing rat 9L gliosarcoma under normal air and carbogen breathing conditions prior to and after i.v. administration of a perflubron emulsion. When these animals were treated with the anti-angiogenic agents TNP-470 and minocycline for 5 days prior to oxygen measurement, tumor hypoxia was decreased compared with untreated tumors. Hypoxia, defined as the percent of pO2 readings < or = 5 mm Hg, was decreased from 71% in untreated air-breathing controls to 34% in animals treated with the anti-angiogenic agents, the perflubron emulsion and carbogen breathing. These effects were manifest in the increased response of the tumor to single-dose (10, 20 and 30 Gy) radiation therapy. Twenty-four hours after treatment with BCNU oxygenation of the tumors was not altered; however, 24 hr after administration of adriamycin oxygenation of the tumors was increased such that hypoxia in adriamycin-treated tumors in animals receiving the perflubron emulsion and carbogen was reduced to 21%. Tumor growth delay in the s.c. tumors was increased by the addition of treatment with the anti-angiogenic agents from day 4 through day 18 post-tumor cell implantation along with BCNU or adriamycin on days 7-11. Administration of the perflubron emulsion and carbogen breathing resulted in increased tumor growth delay with the chemotherapeutic agents alone and in combination with the anti-angiogenic agents. Life span in animals bearing intracranially implanted 9L gliosarcoma progressively increased with administration of the anti-angiogenic agents and then the anti-angiogenic agents and perflubron emulsion/carbogen compared to treatment with BCNU or adriamycin.

The role of minocycline in the treatment of intracranial 9L glioma

This study was designed to explore the question of whether minocycline, a semisynthetic tetracycline shown to inhibit tumor-induced angiogenesis, could control the growth of the rat intracranial 9L gliosarcoma. Minocycline was tested alone and in combination with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) in vivo. Treatment was started at the time of intracranial implantation of 9L gliosarcoma into male Fischer 344 rats, 5 days later, or after tumor resection. Minocycline was delivered locally with a controlled-release polymer or systemically by intraperitoneal injection. Systemic minocycline did not extend survival time. Local treatment with minocycline by a controlled-release polymer implanted at the time of tumor implantation extended median survival time by 530% (p < 0.001) compared to treatment with empty polymer. When treatment was begun 5 days after tumor implantation, minocycline delivered locally or systemically had no effect on survival. However, after tumor resection, treatment with locally delivered minocycline resulted in a 43% increase in median survival time (p < 0.002) compared to treatment with empty polymer. Treatment with a combination of minocycline delivered locally in a controlled-release polymer and systemic BCNU 5 days after tumor implantation resulted in a 93% extension of median survival time compared to BCNU alone (p < 0.002). In contrast, treatment with a combination of systemic minocycline and BCNU did not increase survival time compared to systemic BCNU alone. These results demonstrate that minocycline affects tumor growth when delivered locally and suggest that minocycline may be a clinically effective modulator of intracranial tumor growth when used in combination with a chemotherapeutic agent and surgical resection.

Long-term survival of rats harboring brain neoplasms treated with ganciclovir and a herpes simplex virus vector that retains an intact thymidine kinase gene

Survival of rats harboring cerebral 9L gliosarcomas can be significantly extended by an intratumoral inoculation with a herpes simplex virus vector, designated as hrR3. This vector, which bears the lacZ reporter gene, is defective in the gene encoding ribonucleotide reductase, allowing for replication in dividing tumor cells but not in postmitotic neural cells. It also possesses an intact viral thymidine kinase (TK) gene, which confers chemosensitivity to ganciclovir. In this study, the ability of ganciclovir to potentiate the antitumor effect of hrR3 was evaluated. In culture, there was a 23% decrease in the growth of 9L cells treated with hrR3 plus ganciclovir compared to hrR3 alone (P < 0.01). The combination of hrR3 plus ganciclovir led to the long-term survival of 48% of rats harboring intracerebral 9L gliosarcomas compared to 20% survival in the hrR3 group (P < 0.05). Ganciclovir treatment had no effect on the growth of tumor cells in vitro or in vivo when a herpes simplex virus vector with a defective TK gene was used. Immunocytochemistry confirmed selective expression of the TK gene in cells within the tumor. These findings indicate that the TK gene can potentiate the antitumor effect of the hrR3 herpes simplex virus vector and provide the basis for placing additional therapeutic genes in the genome of hrR3.

Growth inhibition, tumor maturation, and extended survival in experimental brain tumors in rats treated with phenylacetate

Phenylacetate is a naturally occurring plasma component that suppresses the growth of tumor cells and induces differentiation in vitro. To evaluate the in vivo potential and preventive and therapeutic antitumor efficacy of sodium phenylacetate against malignant brain tumors, Fischer 344 rats (n = 50) bearing cerebral 9L gliosarcomas received phenylacetate by continuous s.c. release starting on the day of tumor inoculation (n = 10) using s.c. osmotic minipumps (550 mg/kg/day for 28 days). Rats with established brain tumors (n = 12) received continuous s.c. phenylacetate supplemented with additional daily i.p. dose (300 mg/kg). Control rats (n = 25) were treated in a similar way with saline. Rats were sacrificed during treatment for electron microscopic studies of their tumors, in vivo proliferation assays, and measurement of phenylacetate levels in the serum and cerebrospinal fluid. Treatment with phenylacetate extended survival when started on the day of tumor inoculation (P < 0.01) or 7 days after inoculation (P < 0.03) without any associated adverse effects. In the latter group, phenylacetate levels in pooled serum and cerebrospinal fluid samples after 7 days of treatment were in the therapeutic range as determined in vitro (2.45 mM in serum and 3.1 mM in cerebrospinal fluid). Electron microscopy of treated tumors demonstrated marked hypertrophy and organization of the rough endoplasmic reticulum, indicating cell differentiation, in contrast to the scant and randomly distributed endoplasmic reticulum in tumors from untreated animals. In addition, in vitro studies demonstrated dose-dependent inhibition of the rate of tumor proliferation and restoration of anchorage dependency, a marker of phenotypic reversion. Phenylacetate, used at clinically achievable concentrations, prolongs survival of rats with malignant brain tumors through induction of tumor differentiation. Its role in the treatment of brain tumors and other cancers should be explored further.