Changing incidence and improved survival of gliomas
Introduction
Gliomas form a heterogeneous group of tumours of neuroepithelial tissue which comprise the majority of malignancies of the central nervous system (CNS) [1], [2], [3]. On the basis of their histopathology, gliomas are classified into astrocytoma, oligodendroglioma, oligoastrocytoma (or ‘mixed’ glioma) and ependymoma, and subdivided into grade I–IV according to the World Health Organisation (WHO) grading system [4]. Gliomas represent a relatively rare but serious health burden in terms of morbidity and mortality. Despite significant advances in diagnostics and therapeutics over the past decades, prognosis for patients with high-grade gliomas (WHO grade III and IV tumours) remains dismal, with disease generally recurring even after optimal initial treatment. For instance, addition of the alkylating agent temozolomide to the therapeutic arsenal against glioblastoma (WHO grade IV astrocytoma) increased median survival of patients by a mere 2.5 months [5], or 4.6 months in those having undergone complete resection [6].
Notwithstanding their more favourable characteristics, low-grade gliomas (WHO grade I and II tumours) may eventually cause a variety of neurological symptoms including epilepsy and cognitive disorders [7], and some have a marked potential for malignant progression. Unfortunately, complete surgical removal is commonly unfeasible due to diffuse brain infiltration [8], and procedures carry the risk of causing impairment themselves. Optimal treatment strategies have long been subject of debate [9], [10]. While some advocate active surveillance until progression as a reasonable option [11], [12], notably in (younger) patients who experience seizures as the only symptoms of disease [13], [14], recent guidelines recommend a more active approach, with surgical tumour debulking as the preferred first course of action in most cases [15], [16].
On several occasions, population-based surveys have reported rising incidence of brain tumours including gliomas in adults [17], [18]. These trends should, in retrospect, be largely attributed to improved detection, in particular of low-grade tumours following introduction of computed tomography (CT) and magnetic resonance imaging (MRI) [19], [20], and increased efforts to obtain histopathological diagnosis [21], [22]. Indeed, the observed increase did not coincide with sudden increases in mortality rates [23]. Recent years show a stabilising or even declining incidence [2], [24], [25], [26]. Some caution is warranted in interpreting these findings, however, since trends are sensitive not only to developments in diagnostic and therapeutic practices, but may also be impacted on by changes in histologic criteria and revisions in classification schemes [27], [28].
The present report describes the incidence and survival of CNS gliomas in adults diagnosed in the Netherlands during the time period 1989–2010. In addition, we show survival patterns for the major histological groups of glioma, thereby focusing on glioblastoma and low-grade gliomas.
Section snippets
Data sources
Electronic patient records were derived from the Netherlands Cancer Registry (NCR), which covers a nation with approximately 16.6 million inhabitants. Newly diagnosed cancer patients are notified to the registry by the Dutch Pathology Network (PALGA), to which pathology departments submit their reports on histological, cytological and autopsy examinations. Additional information on patient and tumour characteristics, diagnostics and therapy is collected from hospital records by trained registry
Incidence
Between 1989 and 2010, a total of 21,085 gliomas were registered in the Netherlands, with males comprising the majority across astrocytic and unspecified tumours (Table 2). Overall, the median age at diagnosis was 59 years: while this was 61 years for glioblastoma patients and 71 years for those in whom the disease was not histologically confirmed, median ages for other histologic subtypes were substantially lower. A total of 13,829 patients (66%) presented with an astrocytic tumour and of these,
Discussion
This study reports the incidence and survival of adults diagnosed with a glioma in the Netherlands from 1989 to 2010. As the data are derived from a near complete cancer registry, our analyses provide reliable estimates of their overall disease burden in the Dutch population. By accounting for unspecified neoplasms retrieved on the basis of patient discharge, we may mitigate artificial trends induced by improved imaging and histopathological examination. We cannot preclude, however, that some
Conclusions
In summary, the incidence rate for the total group of gliomas including unspecified brain tumours slightly increased, with trends differing between glioma subtypes. Two-year survival rates for glioblastoma have improved over time, mainly since the introduction of combined chemoradiation. Survival improved for low-grade gliomas except for low-grade astrocytic tumours.
Conflict of interest statement
None declared.
References (43)
- et al.
Epidemiology of glial and non-glial brain tumours in Europe
Eur J Cancer
(2012) - et al.
Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomised phase III study: 5-year analysis of the EORTC-NCIC trial
Lancet Oncol
(2009) - et al.
Management of diffuse low-grade cerebral gliomas
Neurol Clin
(2010) - et al.
Temozolomide versus standard 6-week radiotherapy versus hypofractionated radiotherapy in patients older than 60 years with glioblastoma: the Nordic randomised, phase 3 trial
Lancet Oncol
(2012) - et al.
Temozolomide chemotherapy alone versus radiotherapy alone for malignant astrocytoma in the elderly: the NOA-08 randomised, phase 3 trial
Lancet Oncol
(2012) - et al.
Molecular subclasses of high-grade glioma predict prognosis, delineate a pattern of disease progression, and resemble stages in neurogenesis
Cancer Cell
(2006) - Central Brain Tumor Registry of the United States. Statistical Report: Primary Brain and Central Nervous System Tumors...
- et al.
Annual report to the nation on the status of cancer, 1975–2007, featuring tumors of the brain and other nervous system
J Natl Cancer Inst
(2011) - et al.
Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma
N Engl J Med
(2005)
The dilemma of low grade glioma
J Neurol Neurosurg Psychiatry
Diffusely infiltrative low-grade gliomas in adults
J Clin Oncol
Outcome in adult low-grade glioma: the impact of prognostic factors and treatment
Neurology
Suspected low-grade glioma: is deferring treatment safe?
Ann Neurol
Cognitive status and quality of life in patients with suspected versus proven low-grade gliomas
Neurology
Supratentorial low grade astrocytoma: prognostic factors, dedifferentiation, and the issue of early versus late surgery
J Neurol Neurosurg Psychiatry
Current treatment of low grade gliomas
Memo
Guidelines on management of low-grade gliomas: report of an EFNS-EANO Task Force
Eur J Neurol
Comparison of a strategy favoring early surgical resection vs a strategy favoring watchful waiting in low-grade gliomas
JAMA
Brain, other central nervous system, and eye cancer
Cancer
The increasing incidence of malignant gliomas and primary central nervous system lymphoma in the elderly
Cancer
Cited by (171)
BCAS3 accelerates glioblastoma tumorigenesis by restraining the P53/GADD45α signaling pathway
2022, Experimental Cell ResearchCitation Excerpt :Its 5-year case fatality rate is second only to pancreatic and lung cancers among whole body tumors [4]. Although the modern level of medical care has made progress rapidly, including improvements in neurosurgery and the success of various clinical trials testing new drug therapies, the median survival of patients with GBM after the administration of these combined clinical treatments only increased from 8.9 months to 14.2 months [5]. Therefore, an urgent need is for researchers to rapidly determine the best ideas.