Janet M. Bruner

The descriptive epidemiology of craniopharyngioma.

The incidence of craniopharyngioma in the United States was estimated from two population-based cancer registries that include brain tumors of benign and borderline malignancy: the Central Brain Tumor Registry of the United States (CBTRUS) and Los Angeles county. Information on additional pediatric tumors was available from the Greater Delaware Valley Pediatric Tumor Registry (GDVPTR). The overall incidence of craniopharyngioma was 0.13 per 100,000 person years and did not vary by gender or race. A bimodal distribution by age was noted with peak incidence rates in children (aged 5-14 years) and among older adults (aged 65-74 years in CBTRUS and 50-74 years in Los Angeles county). Survival information was available from GDVPTR and the National Cancer Data Base (NCDB), a hospital-based reporting system. In the NCDB, the 5-year survival rate was 80% and decreased with older age at diagnosis. Survival is higher among children and has improved in recent years. Approximately 338 cases of craniopharyngiomas are expected to occur annually in the United States, with 96 occurring in children from 0 to 14 years of age.

Descriptive epidemiology of primary brain and CNS tumors: Results from the Central Brain Tumor Registry of the United States, 1990-1994

The Central Brain Tumor Registry of the United States (CBTRUS) obtained 5 years of incidence data (1990-1994)--including reports on all primary brain and CNS tumors--from 11 collaborating state cancer registries. Data were available for 20,765 tumors located in the brain, meninges, and other CNS sites, including the pituitary and pineal glands. The average annual incidence was estimated at 11.5 cases per 100,000 person-years. The higher incidence of tumors in male patients (12.1 per 100,000 person-years) than in female patients (11.0 per 100,000 person-years) was statistically significant (P < 0.05); the higher incidence in whites (11.6 per 100,000 person-years) compared with blacks (7.8 per 100,000 person-years) was statistically significant (P < 0.05). The most frequently reported histologies were meningiomas (24.0%) and glioblastomas (22.6%). Higher rates for glioblastomas, anaplastic astrocytomas, oligodendrogliomas, anaplastic oligodendrogliomas, ependymomas, mixed gliomas, astrocytomas not otherwise specified, medulloblastomas, lymphomas, and germ cell tumors in male than in female patients were statistically significant (P < 0.05), with relative risks (RR) ranging from 1.3 to 3.4. Meningiomas were the only tumors with a significant excess in females (RR = 0.5). We noted higher occurrence rates in whites than in blacks for the following histologies: diffuse astrocytomas, anaplastic astrocytomas, glioblastomas, oligodendrogliomas, ependymomas, mixed gliomas, astrocytomas NOS, medulloblastomas, nerve sheath tumors, hemangioblastomas, and germ cell tumors, with RRs ranging from 1.5 to 3.4. Racial differences in occurrence rates were not observed for predominately benign meningiomas or pituitary tumors. This study represents the largest compilation of data on primary brain and CNS tumors in the United States. Standard reporting definitions and practices must be universally adopted to improve the quality and use of cancer registry data.

Comparison of cell adhesion molecule expression between glioblastoma multiforme and autologous normal brain tissue

We investigated glioblastoma multiforme (GBM) for a pattern of consistent alterations in cell adhesion molecules (CAM) expression that might distinguish tumor from normal autologous brain tissue. We used frozen section immunohistochemistry with anti-CAM and computerized image analysis to quantify staining intensity which we expressed as relative intensity units (RIU). Our results showed that normal brain tissue generally did not express alpha 1 beta 1, intercellular CAM-1 (ICAM-1), and sialylated Lewisx, slightly expressed alpha 2, alpha 4, alpha 5, alpha 6 beta 1, alpha v beta 3, lymphocyte function-associated antigen-3 (LFA-3), Lewisx, sialylated LewisLewisx, had a good expression of alpha 3 beta 1 and CD44, and strongly expressed neural CAM (NCAM). GBM expressed alpha 2, alpha 3, alpha 5, alpha 6 beta 1, alpha v beta 3, ICAM-1, LFA-3, CD44, Lewisx, sialylated Lewisx, and sialylated LewisLewisx significantly higher (2-11-fold RIU) than normal brain tissue. ICAM-1 and LFA-3 were the most distinctive markers of GBM. The small blood vessel endothelial cells of the normal brain and the GBM showed a few differences. The tumor endothelium expression of alpha 2 beta 1, alpha 4 beta 1, and LFA-3 RIU appeared twice higher than in normal endothelium and alpha 6 beta 1 showed an average of 40% RIU decrease in comparison to normal. These results show that the expression of several CAM is consistently altered in GBM and its microvasculature when compared with autologous normal brain tissue.

Outcome and patterns of failure following limited-volume irradiation for malignant astrocytomas

Between January 1982 and June 1986, 60 consecutive patients with high-grade astrocytomas [39 glioblastoma multiforme (GBM), 21 anaplastic astrocytoma (AA)] were treated with radiation therapy after biopsy (13 patients) or resection (47 patients). Fifty-three patients were treated with limited-volume irradiation, and seven patients received whole-brain irradiation. The mean tumor dose was 65.4 Gy. In 35 patients, chemotherapy was given as part of their initial treatment. The 1- and 2-year survivals for GBM patients were 40 and 14%, respectively. Survival figures for AA patients were 76 and 52% at 1 and 2 years, respectively. The progression-free rate at 1 year was 13% in GBM and 29% in AA patients. Thirty-four of 48 patients who received limited-volume irradiation had evidence of progression on postirradiation CT scans. Six patients (3 GBM, 3 AA) had evidence of a new intracranial metastatic site on CT scan. In three patients the metastasis was within the previously irradiated volume, and in the other three patients, it was outside this volume. All six had evidence of progression of their primary tumor at the original location on CT scan prior to the discovery of the metastatic site. Twenty-one patients (15 GBM, 6 AA) had at least one postirradiation reoperation for a recurrent mass. Nineteen patients had recurrent tumors in the primary site, and two patients had necrosis but no tumor. Patients who received limited-volume irradiation for high-grade astrocytomas achieved the same survival results as patients treated previously with whole brain irradiation. New intracranial metastases did not influence the outcome, since these were always antedated by tumor progression at the primary site.

The treatment of recurrent unresectable and malignant meningiomas with interferon alpha-2B

OBJECTIVE Recurrent malignant meningiomas and unresectable meningiomas represent a great therapeutic challenge after the failure of radiation therapy. No effective chemotherapy has been found. We report the preliminary results of the treatment of patients with recurrent unresectable or malignant meningiomas with recombinant interferon alpha-2B (IFN-alpha-2B). METHOD Each of six patients with either a recurrent malignant meningioma or an unresectable meningioma was treated with IFN-alpha, administered subcutaneously at a dosage of 4 mU/m2 per day, 5 days per week. Two of the six meningiomas were regular, one was atypical, and three were malignant. RESULTS Five of six patients exhibited positive response to treatment; with stabilization of the size of the tumor in four patients and slight regression in one. The responses observed lasted from 6 to 14 months. The toxicity associated with prolonged use of IFN-alpha was mild and well tolerated. CONCLUSION These results suggest that IFN-alpha is effective in the treatment of recurrent malignant meningiomas.

Predominance of a type 2 intratumoural immune response in fresh tumour-infiltrating lymphocytes from human gliomas.

Increasing evidence suggests the existence of polarized human T cell responses described as Th1‐type (promoting cell‐mediated immunity) and Th2‐type (promoting humoral immunity), characterized by a dominant production of either interferon‐gamma (IFN‐γ) or IL‐4, respectively. Little is known about the intratumoural activation of infiltrating lymphocytes (TIL) in human gliomas. Therefore, we assessed fresh TIL at cellular and molecular levels to find out if they were activated and polarized into a type 1 or 2 immune response. Flow cytometry analysis of TIL revealed that the major subset was made of T lymphocytes. Double labelling with α‐CD3 and adhesion/activation markers revealed T cell subsets expressing CD49a, CD49b, CD54, and CD15, some of which were almost absent in autologous T peripheral blood lymphocytes (T‐PBL). Furthermore, the proportions of T‐TIL expressing CD56, CD65, or CD25 were several‐fold higher than in T‐PBL. Intratumoural functional activation of TIL was tested by semiquantitative assessment in relative units (RU) of lymphokine gene activation with mRNA reverse transcriptase‐polymerase chain reaction (RT‐PCR). All TIL populations except one significantly expressed IL‐4 1 to 2 logs of RU above healthy PBL baseline. Similarly, all patients expressed granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) in a range comparable to IL‐4. However, most TIL populations did not express IFN‐γ, IL‐2, and tumour necrosis factor‐beta (TNF‐β) at higher levels than healthy normal PBL. The increased proportion of T cells expressing activation markers and the consistent detection of significant IL‐4 and GM‐CSF lymphokine gene activation in TIL populations suggested a predominant type 2 intratumoural immune response that does not promote cell‐mediated tumouricidal activity and may contribute to the inefficiency of the antiglioma immune response.

Basic fibroblast growth factor and fibroblast growth factor receptor I are implicated in the growth of human astrocytomas

SummaryMalignant astrocytomas are highly invasive, vascular neoplasms that comprise the majority of nervous system tumors in humans. A strong association has previously been made between malignancy in human astrocytic tumors and increased expression of certain fibroblast growth factor (FGF) family members, including basic and acidic FGF. The influence of endogenous basic FGF on glioblastoma cell growthin vitro was evaluated using basic FGF-specific antisense oligonucleotides. These studies indicated that human glioblastoma cell growthin vitro, can be inhibited by suppressing basic FGF expression. Human astrocytomas also exhibited changes in FGF receptor (FGFR) expression during the course of their progression from a benign to a malignant phenotype. FGFR2 (bek) expression was abundant in normal white matter and in all low grade astrocytomas, but was not observed in glioblastomas. Conversely, FGFR1 (flg) expression was absent or barely detectable in normal white matter, but was significantly elevated in glioblastomas. Glioblastomas also expressed an alternatively spliced form of FGFR1 containing two immunoglobulin-like disulfide loops (FGFR1β), whereas normal human adult and fetal brain expressed a form of the receptor containing three immunoglobulin-like disulfide loops (FGFR1α). Intermediate grades of astrocytic tumors exhibited a gradual loss of FGFR2 and a shift in expression from FGFR1α to FGFR1β as they progressed from a benigh to a malignant phenotype. The underlying cytogenetic changes that contribute to these alterations are not entirely understood, but abnormalities in the p53 tumor suppressor gene may influence expression of bFGF as well as the FGFR. These results suggest that alterations in FGFR signal transduction pathways may play a critical role in the malignant progression of astrocytic tumors.

Assessment and prognostic significance of mitotic index using the mitosis marker phospho-histone H3 in low and intermediate-grade infiltrating astrocytomas.

Distinguishing between grade II and grade III diffuse astrocytomas is important both for prognosis and for treatment decision-making. However, current methods for distinguishing between grades based on proliferative potential are suboptimal, making identification of clear cutoffs difficult. In this study, we compared the results from immunohistochemical staining for phospho-histone H3 (pHH3), a specific marker of cells undergoing mitosis, with standard mitotic counts (number of mitoses/10 high-power fields) and MIB-1 labeling index values for assessing proliferative activity. We tested the relationship between pHH3 staining and tumor grade and prognosis in a retrospective series of grade II and III infiltrating astrocytomas from a single institution. The pHH3 index (per 1000 cells), MIB-1 index (per 1000 cells), and number of mitoses per 10 high-power fields were determined for each of 103 cases of grade II and III diffuse astrocytomas from patients with clinical follow-up. pHH3 staining was found to be a simple and reliable method for identifying mitotic figures, allowing a true mitotic index to be determined. The pHH3 mitotic index was significantly associated both with the standard mitotic count and with the MIB-1 index. Univariate analyses revealed that all 3 measurements of proliferation were significantly associated with survival. However, the pHH3 mitotic index accounted for a larger proportion of variability in survival than standard mitotic count or MIB-1/Ki-67 labeling index. After adjusting for age, extent of resection, and performance score, the pHH3 mitotic index remained an independent predictor of survival. Thus, pHH3 staining provides a simple and reliable method for quantifying proliferative potential and for the stratification of patients with diffuse astrocytomas into typical grade II and III groups. These results also suggest that pHH3 staining may be a useful method in other neoplasms in which accurate determination of proliferation potential is relevant to tumor grading or clinical treatment decision-making.

Astrocytes derived from p53-deficient mice provide a multistep in vitro model for development of malignant gliomas.

Loss or mutation of p53 is thought to be an early event in the malignant transformation of many human astrocytic tumors. To better understand the role of p53 in their growth and transformation, we developed a model employing cultured neonatal astrocytes derived from mice deficient in one (p53 +/-) or both (p53 -/-) p53 alleles, comparing them with wild-type (p53 +/+) cells. Studies of in vitro and in vivo growth and transformation were performed, and flow cytometry and karyotyping were used to correlate changes in growth with genomic instability. Early-passage (EP) p53 -/- astrocytes achieved higher saturation densities and had more rapid growth than EP p53 +/- and +/+ cells. The EP p53 -/- cells were not transformed, as they were unable to grow in serum-free medium or in nude mice. With continued passaging, p53 -/- cells exhibited a multistep progression to a transformed phenotype. Late-passage p53 -/- cells achieved saturation densities 50 times higher than those of p53 +/+ cells and formed large, well-vascularized tumors in nude mice. p53 +/- astrocytes exhibited early loss of the remaining wild-type p53 allele and then evolved in a manner phenotypically similar to p53 -/- astrocytes. In marked contrast, astrocytes retaining both wild-type p53 alleles never exhibited a transformed phenotype and usually senesced after 7 to 10 passages. Dramatic alterations in ploidy and karyotype occurred and were restricted to cells deficient in wild-type p53 following repeated passaging. The results of these studies suggest that loss of wild-type p53 function promotes genomic instability, accelerated growth, and malignant transformation in astrocytes.

Molecular classification of human diffuse gliomas by multidimensional scaling analysis of gene expression profiles parallels morphology-based classification, correlates with survival, and reveals clinically-relevant novel glioma subsets

There are several currently employed classification systems for diffuse gliomas that sort tumors based on histological features. Contemporary molecular techniques, however, offer the promise of improved tumor classification and resultant patient stratification for treatment and prognosis. In particular, gene expression profiling has shown exceptional promise for providing an alternative and more objective molecular approach to glioma classification. In this study, we used cDNA array technology to profile the gene expression of 30 primary human glioma tissue samples comprising 4 different glioma subtypes as defined by current World Health Organization (WHO 2000) criteria: glioblastoma (GM, WHO grade IV), anaplastic astrocytoma (AA, WHO grade III), anaplastic oligodendroglioma (AO, WHO grade III), and oligodendroglioma (OL, WHO grade II). Gene expression data alone were used to group the tumors using multidimensional scaling, which is an unsupervised statistical method. Results show that impressive separation of the 4 glioma subtypes can be achieved solely on the basis of molecular data. In addition, a subcluster of 3 glioblastomas was identified as distinct from other GMs and from the oligodendroglial tumors. These 3 patients have shown extended survival compared to other GMs in the study. Survival analysis of the full data set revealed a good correlation with the molecular classification. Results of this proof‐of‐principle study demonstrate that molecular profiling alone can recapitulate conventional histologic classification and grading with high fidelity. In addition, results show that the molecular approach to tumor classification can generate clinically meaningful patient stratification, and, more importantly, is an efficient class‐discovery tool for human gliomas, permitting the identification of previously unrecognized, clinically relevant tumor subsets.