International Journal of Radiation Oncology*Biology*Physics
Clinical InvestigationAdult Supratentorial Low-Grade Glioma: Long-Term Experience at a Single Institution
Introduction
It has been estimated that in the United States, approximately 17,000 primary central nervous system tumors are diagnosed annually (1). Of these primary tumors, almost one-half are tumors of neuroepithelial origin, with approximately one-quarter of these classified as low-grade gliomas (1). Patients affected by these tumors are often young and treatment decisions should include consideration of the potential indolent nature of these tumors and the potential long-term side effects of available therapies. Therefore, the question of the optimal treatment of patients with low-grade gliomas continues to generate considerable controversy. Retrospective studies have helped to delineate prognostic factors for patients with these tumors, as well as the relative efficacy of surgery, radiotherapy, and chemotherapy (2). The results of recently completed and ongoing, prospective, multi-institutional trials will also help to guide the treatment of these patients in the future by clarifying the role radiotherapy and chemotherapy and through the development of prognostic models for patients with these tumors 3, 4, 5. Despite these advances, the follow-up in these prospective trials remains relatively short for a group of tumors with known indolent behavior and protracted clinical course. We have previously reported on a cohort of adult patients with supratentorial low-grade glioma treated at the London Regional Cancer Program in the 1980s to mid-1990s (6). Although the median follow-up in our initial report was close to 5 years (50 months), we chose to update this original cohort of patients to examine the long-term outcomes and re-evaluate the previously identified prognostic indicators in the setting of extended follow-up.
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Methods and Materials
For both the original report and the present analysis, the data were abstracted from the patients' charts and included the existing radiology, pathology, and clinical reports. Central radiology and pathology review was not attempted for the present analysis. The data abstracted from the chart included gender, date of first symptoms, date of first imaging study demonstrating tumor, symptoms at presentation, date of tissue diagnosis, tumor location (according to the radiology report), presence of
Results
From our original cohort of 167 patients, we excluded 22 from the present analysis. Of these 22 patients, 17 were excluded as lost to follow-up (most of these patients had come for a second opinion or had undergone surgery only without follow-up at our institution). Five patients were excluded because they had a pathology review subsequent to the original report that revealed a histologic type other than Grade 2 astrocytoma, oligodendroglioma, or mixed glioma.
The median follow-up for the
Discussion
We restricted our review to adult patients with World Health Organization Grade 2 oligodendroglioma, astrocytoma, or mixed oligoastrocytoma (13) treated between 1980 and 1995. A clear limitation of our study was the absence of central pathology and radiology review for our patients. Interobserver variability in the diagnosis and grading of gliomas has been well documented, even in modern series (14). Coons et al.(15) observed that even with well-defined criteria, expert observers, and formal
Conclusion
The findings from our long-term cohort have reaffirmed the importance of previously identified prognostic variables. Approximately 50% and 20% of patients were alive at 10 and 20 years after the first diagnosis. Of the long-term survivors, the quality of life (at least as assessed retrospectively) was good. This information could be useful in counseling low-grade glioma patients regarding their long-term outlook.
Acknowledgments
The authors wish to extend their thanks to Frances Whiston and Larry Stitt for biostatistical support and Christopher Leighton, M.D., for his work on the original database.
References (28)
- et al.
Measuring the quality of life of cancer patients: A concise QL-index for use by physicians
J Chronic Dis
(1981) - et al.
Interobserver reproducibility among neuropathologists and surgical pathologists in fibrillary astrocytoma grading
J Neurol Sci
(2000) - et al.
Long-term efficacy of early versus delayed radiotherapy for low-grade astrocytoma and oligodendroglioma in adults: The EORTC 22845 randomised trial
Lancet
(2005) - et al.
Radiation response of the central nervous system
Int J Radiat Oncol Biol Phys
(1995) - et al.
Management of patients with low-grade gliomas
Neurol Clin
(2007) Statistical report: Primary brain tumors in the United States, 1992–1997
(2000)Looking through the retrospectoscope in the era of evidence-based medicine
J Clin Oncol
(1997)- et al.
Prospective randomized trial of low- versus high-dose radiation therapy in adults with supratentorial low-grade glioma: Initial report of a North Central Cancer Treatment Group/Radiation Therapy Oncology Group/Eastern Cooperative Oncology Group study
J Clin Oncol
(2002) - et al.
Final report of Radiation Therapy Oncology Group (RTOG) protocol 9802: Radiation therapy (RT) versus RT + procarbazine, CCNU, and vincristine (PCV) chemotherapy for adult low-grade glioma (LGG)
(2008) - et al.
Prognostic factors for survival in adult patients with cerebral low-grade glioma
J Clin Oncol
(2002)
Supratentorial low-grade gliomas in adults: An analysis of prognostic factors and timing of radiation
J Clin Oncol
Non-parametric estimation from incomplete observations
J Am Stat Assoc
Statistical methods for survival data analysis
The clinical evaluation of chemotherapeutic agents in cancer
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Conflict of interest: none.