Neoplasms of the central nervous system in Norway

Epidemiology of Glioblastoma Multiforme-Literature Review

Glioblastoma multiforme (GBM) is one of the most aggressive malignancies, with a median overall survival of approximately 15 months. In this review, we analyze the pathogenesis of GBM, as well as epidemiological data, by age, gender, and tumor location. The data indicate that GBM is the higher-grade primary brain tumor and is significantly more common in men. The risk of being diagnosed with glioma increases with age, and median survival remains low, despite medical advances. In addition, it is difficult to determine clearly how GBM is influenced by stimulants, certain medications (e.g., NSAIDs), cell phone use, and exposure to heavy metals.

Long-Term Survival in Cerebral Glioblastoma. Case Report and Critical Review of the Literature

Glioblastoma multiforme is the most malignant tumor of the glial series. The average survival of patients with this tumor ranges from 6 to 12 months. The case of a patient who survived for more than 11 years after diagnosis of a temporal-occipital glioblastoma which was treated with surgery, radiotherapy and chemotherapy is described. The authors deduce that among patients with glioblastoma multiforme (GM), those with a long disease-free interval after initial diagnosis who undergo multimodal therapy, including aggressive tumor removal, are the most likely long-term survivors (LS). Other factors which appeared to be related to longer survival were younger age and high Karnofsky scores.

Incidence of and survival from oligodendroglioma in Denmark, 1943-2002

We established the nationwide, population-based incidence of oligodendroglioma in Denmark during 59 years of monitoring and compared the overall survival of patients with oligodendroglial tumors during the periods 1943-1977 and 1978-2002. On the basis of reports in the Danish Cancer Registry, 1,304 cases of oligodendroglioma were included in the study. We calculated sex- and age-specific incidence rates in 5-year age intervals and for 5-year calendar periods. Overall survival was estimated by the Kaplan-Meier method. In the period 1943-2002, the incidence rate of oligodendroglioma was less than 1 case per 100,000 person-years, but varied somewhat when viewed across isolated periods. Comparison of the incidence rate before and after the introduction of CT scanning did not reveal a significant difference in the incidence rate. The median survival increased from 1.4 years (95% confidence interval [CI], 1.0-1.6) to 3.4 years (95% CI, 2.6-4.2) during the period of study. The overall incidence of oligodendroglioma showed a relatively stable pattern over nearly 60 years of monitoring. Overall survival improved significantly during the study period, which could partly be due to improved diagnostic methods and treatment options.

Molecular pathogenesis of adult brain tumors and the role of stem cells

Primary brain tumors consist of neoplasms with varied molecular defects, morphologic phenotypes, and clinical outcomes. The genetic and signaling abnormalities involved in tumor initiation and progression of the most prevalent adult primary brain tumors, including gliomas, meningiomas, and medulloblastomas, are described in this article. The current understanding of the cell-of-origin of these neoplasms is reviewed, which suggests that the malignant phenotype is propelled by cells with stem-like qualities. A comprehensive understanding of the molecular basis of transformation and the cell-of-origin of these neoplasms will enable the formulation of more targeted treatment alternatives that could improve survival and quality of life.

Oligodendroglial-specific transcriptional factor SOX10 is ubiquitously expressed in human gliomas

The two most common types of gliomas: astrocytoma and oligodendroglioma are distinguished based on their morphologic similarities to mature astrocytes and oligodendroglia. Whereas prototypical examples of the tumors have distinct pathogenetic and prognostic differences, the majority of the gliomas falls in the intermediate category and their distinction is problematic. The transcriptional factor SOX10 is one of the key determinants of oligodendroglial differentiation. We applied immunohistochemistry to analyze whether the expression of SOX10 can differentiate astrocytoma and oligodendroglioma. The majority of oligodendrogliomas, but also a large fraction of astrocytomas, including the least differentiated glioblastomas, expressed SOX10, albeit at lower levels. Comparison with 1p and 19q deletion status by FISH analysis also revealed no obvious associations. High levels of expression were also found in pilocytic astrocytoma, consistent with recent studies suggesting that pilocytic astrocytomas have greater overlap with oligodendroglial than astrocytic tumors. Our data raise a possibility that histogenesis of gliomas have more common features than previously anticipated.

From the archives of the AFIP: Oligodendroglioma and its variants: radiologic-pathologic correlation

Oligodendroglioma is the third most common glial neoplasm and most commonly arises in the frontal lobe. It occurs in males more frequently, and the peak manifestation is during the 5th and 6th decades. Children are affected much less commonly. The clinical presentation is often of several years duration with most patients presenting with seizures, reflecting the strong predilection of this tumor to involve the cortical gray matter. Current histopathologic classification schemes recognize two main types of tumors: well-differentiated oligodendroglioma and its anaplastic variant. Less commonly, neoplastic mixtures of both oligodendroglial and astrocytic components occur and are termed oligoastrocytomas, with both well-differentiated and anaplastic forms. Surgical resection is the mainstay of initial treatment, and many patients experience a long progression-free period. Recent genotyping has revealed chromosomal loss of 1p and 19q as a genetic signature in most oligodendrogliomas, and these tumors respond favorably to chemotherapy. Hence, radiation therapy is now generally reserved for partially resected tumors and cases that failed to benefit from chemotherapy. At cross-sectional imaging, the tumor characteristically involves the cortical gray matter and frequently contains calcification. Robust enhancement is not a common feature and suggests transformation to a higher histologic grade. Advanced magnetic resonance imaging techniques and metabolic imaging play increasingly important roles in both pre- and postoperative assessment of these complex neoplasms.

Functional endothelin ET B receptors are selectively expressed in human oligodendrogliomas

Endothelin-1 (ET-1), a vasoactive and mitogenic peptide mainly produced by vascular endothelial cells, may be involved in the progression of several human tumors. Here, we present an immunohistochemical analysis of the expression pattern of ET-1 receptor subtypes (ET(A)-R and ET(B)-R) and a functional study of their potential role in human oligodendrogliomas and oligoastrocytomas. By comparison, we assessed the corresponding expression patterns of glioblastomas. Interestingly, a nuclear localization of ET-1 receptor subtypes (associated or not with a cytoplasmic labeling) was constantly observed in tumor cells from all three glioma types. Moreover, we noted a distinct receptor distribution in the different gliomas: a nuclear expression of ET(B)-R by tumor cells was found to be restricted to oligodendrogliomas and oligoastrocytomas, while a nuclear expression of ET(A)-R was only detected in tumor cells from some glioblastomas. Using primary cultures of oligodendroglial tumor cells, we confirmed the selective expression of nuclear ET(B)-R, together with a plasma membrane expression, and further demonstrated that this receptor was functionally coupled to intracellular signaling pathways known to be involved in cell survival and/or proliferation: extracellular signal-regulated kinase and focal adhesion kinase activation, actin cytoskeleton reorganization. In addition, impairment of ET(B)-R activation in these cells by in vitro treatment with an ET(B)-R-specific antagonist induced cell death. These data point to ET-1 as a possible survival factor for oligodendrogliomas via ET(B)-R activation and suggest that ET(B)-R-specific antagonists might constitute a potential therapeutic alternative for oligodendrogliomas.

Pathology and molecular genetics of oligodendroglial tumors

Oligodendroglial gliomas are second only to astrocytic gliomas in frequency. The lack of stringent diagnostic criteria cause high interobserver variation in regard to classification and grading of these tumors. Previous studies have described oligodendrogliomas with features that overlap with those of neurocytic tumors, thus further complicating diagnostic decisions. The increasing need for standardized diagnostic criteria in this subset of gliomas is emphasized by the benefit of adjuvant therapies in patients with anaplastic oligodendrogliomas. Characteristic chromosomal aberrations have been successfully determined for oligodendroglial tumors in recent years. In contrast to astrocytomas, however, no genes in the affected regions have been clearly linked to their pathogenesis. However, the molecular findings promise to be helpful for diagnostic and therapeutic decisions. This review compiles clinical, pathological, and molecular genetic findings on WHO grades II and III oligodendrogliomas and oligoastrocytomas.

Intraventricular gliomas

Gliomas are the most common primary brain tumor in adults, and those within or relating to the ventricular surface represent a less common but important subcategory. The most common intraventricular gliomas include ependymomas, SEs, and SEGAs. Other less common varieties have been reported, including chordoid gliomas, glioblastoma multiforme, and mixed glial-neuronal tumors. Each type of intraventricular glioma is associated with its own unique constellation of epidemiologic, clinical, radiologic, and pathologic defining characteristics. Each tumor type has its own management considerations and nuances with unique prognostic indicators and outcomes. The outcome for certain intraventricular gliomas (especially ependymomas) remains relatively poor. Future advancements in surgical technique are likely to have only a modest impact on improvement of outcome. Translational research aiming to advance the knowledge of tumor biology into new targeted cellular and molecular therapies holds tremendous promise to improve the overall outcome. Additionally, more thorough delineation of prognostic factors as well as modifications and refinements to radiation and chemotherapy may help to improve the still significantly poor outcomes for patients harboring these lesions. Future cooperative intra- and interinstitutional efforts between scientists and clinicians will hopefully culminate in an improved outlook and eventual cure for patients with gliomas.

Incidence trends of adult primary intracerebral tumors in four Nordic countries

Brain tumors are some of the most lethal adult cancers and there is a concern that the incidence is increasing. It has been suggested that the reported increased incidence can be explained by improvements in diagnostic procedures, although this has not been totally resolved. The aim of our study was to describe the incidence trends of adult primary intracerebral tumors in four Nordic countries during a period with introduction of new diagnostic procedures and increasing prevalence of mobile phone users. Information about benign and malignant primary intracerebral tumor cases 20-79 years of age was obtained from the national cancer registries in Denmark, Finland, Norway and Sweden for the years 1969-98 and estimates of person-years at risk were calculated from the information obtained from national population registries. Annual age standardized incidence rates per 100,000 person-years were calculated and time trends analyses were carried out using Poisson regression. The overall incidence of all intracerebral tumors ranged from 8.4-11.8 for men and 5.8-9.3 for women, corresponding to an average annual increase of 0.6% for men (95% confidence interval [CI] = 0.4, 0.7) and 0.9% for women (95% CI = 0.7, 1.0). The increase in the incidence was confined to the late 1970s and early 1980s and coinciding with introduction of improved diagnostic methods. This increase was largely confined to the oldest age group. After 1983 and during the period with increasing prevalence of mobile phone users, the incidence has remained relatively stable for both men and women.

Incidences of gliomas and meningiomas in Denmark, 1943 to 1997

OBJECTIVE

The objective of this study was to determine the nationwide, population-based incidences of intracranial gliomas and meningiomas (of all grades) during 55 years of monitoring in Denmark.

METHODS

On the basis of reports in the Danish Cancer Registry, we calculated age-standardized, period-specific incidences and age- and birth cohort-specific incidences, in 5-year age and calendar intervals, for intracranial gliomas and meningiomas.

RESULTS

The incidence of gliomas increased 1.7-fold from 1943 to 1947 to 1993 to 1997, whereas the incidence for meningiomas increased 3.9-fold during the same period.

CONCLUSION

Based on complete notification to the Danish Cancer Registry, the overall incidences of intracranial gliomas and meningiomas increased during a 55-year period. These increases were observed for all age groups and both sexes. These increases could be explained on the basis of improved diagnoses of these tumors. For gliomas, a maximal annual incidence of approximately 4 cases/100,000 population (World Standard Population) was observed in Denmark at the end of the study period, suggesting that the effects of improved diagnostic tools have reached their maximum with respect to this tumor type. The same was not observed for the incidence of meningiomas, suggesting that perhaps underreporting is still present.

Expression of human neurotropic polyomavirus JCV late gene product agnoprotein in human medulloblastoma

BACKGROUND

The human neurotropic polyomavirus, JCV, contains an open reading frame within the late region of the viral genome that encodes a 71-amino-acid protein, agnoprotein. Because accumulating evidence supports an association between JCV infection and human brain tumors, including medulloblastomas, we assessed the presence of JCV Agno gene sequences and the expression of agnoprotein in a series of 20 well-characterized medulloblastomas.

METHODS

Formalin-fixed, paraffin-embedded tumor tissue samples were used for Agno gene amplification and for immunohistochemical analysis. Adjacent sections were stained with an antibody to agnoprotein and with antibodies to cellular structural and regulatory proteins, including the JCV early gene product, T antigen.

RESULTS

Analysis of amplified DNA from paraffin-embedded samples revealed the presence of the Agno gene in 11 (69%) of 16 samples. Immunohistochemical analysis showed cytoplasmic localization and widespread distribution of agnoprotein in the neoplastic cells in 11 (55%) of 20 samples. The JCV early gene product, T antigen, was present in the nucleus of some, but not all, of the neoplastic cells. Some medulloblastoma samples that expressed agnoprotein had no sign of T-antigen expression. p53 was detected in only six of the 11 tumors in which agnoprotein was expressed. None of the 20 samples showed expression of the viral late capsid proteins, ruling out productive infection of the tumor cells with JCV.

CONCLUSIONS

Our data provide evidence that the JCV late gene encoding the auxiliary agnoprotein is expressed in tumor cells. The finding of agnoprotein expression in the absence of T-antigen expression suggests a potential role for agnoprotein in pathways involved in the development of JCV-associated medulloblastomas.

Pediatric supratentorial intraventricular tumors

A variety of mass lesions can arise within or in proximity to the ventricular system in children. These lesions are relatively uncommon, and they present a unique diagnostic and surgical challenge. The differential diagnosis is determined by tumor location in the ventricular system, clinical presentation, age of the patient, and the imaging characteristics of the lesion. In this report the authors provide an introduction to and an overview of the most common pediatric supratentorial intraventricular tumors. The typical radiographic features of each tumor and location preference within the ventricular system are reviewed. Management and treatment considerations are discussed. Examination of tissue samples to obtain diagnosis is usually required for accurate treatment planning, and resection without adjuvant therapies is often curative. The critical management decision frequently involves determining which lesions are appropriate for surgical therapy. Care ful preoperative neuroimaging is extremely useful in planning surgery. Knowledge of the typical imaging characteristics of these tumors can help to determine the diagnosis with relative certainty when a tissue sample has not been obtained, because a small subset of these lesions can be managed expectantly.

Brain cancer incidence in the provinces of Zaragoza and Navarre (Spain): effect of age, period and birth cohort

Several studies have detected increases in malignant brain tumour incidence and mortality rates particularly among the elderly. We analyzed time trends in malignant brain tumors incidence in Zaragoza over the period 1973-1990 and Navarre over the period 1973-1991, two Spanish provinces that have been collecting data through their respective Cancer Registries for the last 20 years, using Poisson regression analysis of age, period of diagnosis and cohort. In general, age-adjusted rates showed a steady rise in both registries, except in the case of females in Navarre, for whom a decrease in risk was observed for the last period, 1988-1991. This increase is a reflection of the rise in incidence experienced by the elderly, since the cohorts successively register rates that are stable over time, and even downward in the case of females in Navarre. The risk run by generations born circa 1920-1930 was the highest encountered. Rates were higher in Navarre in both sexes and for all but the last period in females, when rates on the two registers stood level. Increasingly generalised use of CT scanning and magnetic resonance in the 1980s in Spain, coupled with better and more effective health care access for the elderly, are factors that may well have some bearing on these findings.

Epidemiology of adult medulloblastoma

Medulloblastoma is one of the most common primary tumors of the central nervous system seen in children; in contrast, it is somewhat uncommon in adult age. Due to the infrequent occurrence, data on incidence rates are sparse. The present study was aimed at ascertaining the epidemiological characteristics of medulloblastoma in adult age in Piedmont during the period 1976-1995. Piedmont is a region in northwest Italy, which had a total population of 4.30 millions/year for the period mentioned. From the files of clinical records of patients hospitalized in neurologic and neurosurgical departments, 45 cases (32 males, 13 females) of histologically verified medulloblastoma were recorded. The incidence rate (annual per million) in the whole period studied was 0.5 (95% confidence interval, 0.36-0.67). The incidence rate was high in the age group 15 to 19 years (2.33/million/year) and decreased up to age 40, consistent with the embryonal origin of the tumor. No time-trend of incidence rate was found. Male excess was evident in all age groups and in each time period. Median survival time was 17.6 years; the 5-year survival rate was 69.9%. Survival rate in the present group of adult medulloblastoma is slightly better than that reported in clinical series. A comparison was made with incidence data concerning pediatric medulloblastoma reported in the Registry of Childhood Cancer of Piedmont: from 1980 to 1989, adult medulloblastomas represented 34% of medulloblastomas. The figure is higher than that generally assumed, and indicates that the occurrence of this embryonal tumor in adult age is relevant. Our epidemiological data are consistent with an embryonal origin of medulloblastoma.

Descriptive epidemiology of cerebral gliomas in France

BACKGROUND

Descriptive epidemiology of cerebral gliomas has recently been the subject of several studies, indicating a possible increase in brain tumor rates, particularly in the elderly population.

METHODS

Between 1983 and 1990, 1376 registered patients with diagnoses of malignant astrocytomas, low grade astrocytomas, oligodendrogliomas - mixed oligoastrocytomas, and tumors without histologic confirmation were reviewed in 6 French cancer registries. The incidence rates by histologic type, age, and gender were calculated. The variation of the incidence between 1983 and 1990 was also analyzed.

RESULTS

The highest incidence was observed in the malignant astrocytoma group (2.38/100,000/year) followed by the low grade astrocytoma group (0.54/100,000/year) and the oligodendroglioma - mixed oligoastrocytoma group (0.25/100,000/year). A significant male predominance was observed in the malignant astrocytoma group (male/female [M/F] ratio of 1.59; P < 0.001) and in the group without histologic confirmation (M/F ratio of 2.6; P = 0.008). Between 1983 and 1990, an increasing trend of 5% per year was observed in the incidence of malignant astrocytomas in the population older than 65 years.

CONCLUSIONS

These data confirm the observation made in other countries that the incidence of primary brain tumors (particularly malignant astrocytomas) is increasing in elderly patients.

Delay in the diagnosis of glioblastoma multiforme: is age a factor?

Discrimination in the delivery of health care, based on the age of the patient, is attracting increased attention. We investigated this problem by studying possible age-related delay in diagnosis in patients treated for glioblastoma multiforme (GBM). A total of 213 charts of patients with GBM seen from 1972 to 1992 were evaluated for type and duration of symptom, with 204 charts having sufficient data to be analyzed. The mean and median duration of symptoms for the entire group was 48.9 and 28 days, respectively. No age-related difference in duration of symptoms was noted. In light of the increasing incidence of GBM in patients above 60 years of age, further investigation of other possible areas of age discrimination in patients with GBM is warranted.

The incidence of primary central nervous system neoplasms before and after computerized tomography availability

The observed incidence of primary intracranial neoplasms has increased dramatically among the elderly over the past several years. It is unclear to what extent this increase can be attributed to improved detection by new imaging technology and what portion might represent a true increase in incidence. The first computerized tomography (CT) scanner was operative in Norway in 1975 and became available in all geographical regions within 4 years. The author analyzed incidence data from the population-based Cancer Registry of Norway, placing particular emphasis on the basis for diagnosis (histological, imaging, or clinical findings) for the registrations. In the decade from 1983 to 1992, when the use of CT was widespread, incidence rates of primary intracranial neoplasms for individuals aged 55 to 74 and above 74 years were, respectively, 1.76 (95% confidence interval (CI), 1.63-1.90) and 3.35 (95% CI, 2.70-4.15) times the rates in 1963 to 1972 before CT was available. For persons older than 74 years, the relative incidence increase was 1.98-fold (95% CI, 1.53-2.56) for histologically verified tumors; 15.20 (95% CI, 7.80-29.61) when based on imaging (without histological evidence); and 3.33 (95% CI, 1.93-5.76) when based on clinical diagnosis (without imaging or histological evidence). In this age group, the increase for gliomas was 1.77 (95% CI, 1.18-2.65) and 2.28 (95% CI, 1.53-3.39) for meningioma patients. The present study demonstrates that new imaging technology has improved the diagnostic yield of primary intracranial neoplasms. For those older than 74 years, a large part of the three-fold incidence increase from the pre-CT decade 1963 to 1972 to the post-CT decade 1983 to 1992 can be attributed to improved tumor detection.

Time-trend analysis of mortality from malignant tumors of the nervous system in Spain, 1952-1986

We analyzed time trends in mortality from malignant tumors of the nervous system (MTNS) in the adult Spanish population during the period 1952-1986, using Poisson regression analysis of age at death, year of birth and year of death. During such period, mortality rose especially in the elderly as well as among young and middle-aged men. We found two modest period effects, in both sexes attributed to changes in certification practice. An ascending effect in cohorts born up to 1920 in males and females was attributed to improvements in ascertainment. A positive, progressive, cohort effect in males born post-1920 was detected. Mortality from MTNS in Spain was medium-high with a tendency to rise, most likely due to improvements in diagnosis and registration. From this analysis, the existence of a true increase in incidence of brain glioma among young and middle-aged male adults during recent decades is suggested.