Extent of Surgical Resection Predicts a Favorable Outcome for Children with Malignant Gliomas
Reviewer: Heather Jones, MD
Last Modified: October 9, 2002
Presenter: M. Bucci
Presenter's Affiliation: Department of Radiation Oncology, Hospital of the University of Pennsylvania
Type of Session: Poster
Pediatric patients with high-grade gliomas have been reported to have a better prognosis than their adult counterparts. There is however, relatively very little published data available that explore factors that affect outcome in this aggressive malignancy for the pediatric patient population. This study is a retrospective review, from Hospital of the University of Pennsylvania (HUP) and Children's Hospital of Philadelphia (CHOP) reporting their experience in the treatment of children with non-brainstem, malignant gliomas and determine factors that influence progression-free survival (PFS) and overall survival (OS).
Materials and Methods
- Medical records of all patients with non-brainstem malignant gliomas treated at the Hospital of the University of Pennsylvania (HUP) and Children's Hospital of Philadelphia (CHOP) between 2/89 and 10/00 were retrospectively reviewed.
- A total of 39 patients were included in this study.
- All Histology was confirmed by a neuropathologist at CHOP. MRI's were used to assess tumor at presentation and follow-up.
- Median radiation dose was 55.8 Gy (range: 40-60 Gy); (37 of 39) received chemotherapy.
- Gross total resection (GTR) is defined as more than or equal to 90% removal of tumor on post-operative MRI imaging.
- The male : female ratio was 2:1.
- The median age at diagnosis was 12.3 years (range: 1.1-20.6 years).
- Tumors were located in the basal ganglia/thalamus (n=19), peripheral cerebrum (n=18) and cerebellum (n=2). 26 patients had anaplastic astrocytomas (AA) while 13 patients had glioblastoma multiforme (GBM).
- The median follow-up for the 14 surviving patients is 47.6 months (range: 10.6-125.1 months).
- The median PFS and OS for all patients are 12.2 and 21.3 months, respectively.
- OS rate at 2- and 5-years are 46.8% and 35.3%, respectively, while PFS rate at 2- and 5-years are 38.3% and 26.3%.
- Extent of surgery was the strongest factor predicting outcome with patients that underwent a GTR (n=12) having a median survival of 122.2 months compared with 14.1 months for patients with significant residual disease following surgery (p=0.001).
- The absence of visual symptoms at diagnosis also proved to be a significant predictor of improved OS (p=0.034)
- Patients with GTR had better local control than those with significant residual disease (p = 0.004).
- Eight of 28 patients with evaluable residual tumor following resection had an objective radiologic response to radiation with a median time to maximal response of 4.7 months following completion of radiation
While the extent of resection as a prognosticator has been debated for adult patients, this study suggests that it is one of the strongest predictors of outcome in pediatric patients with high-grade gliomas. Thus, optimal treatment for these patients should include maximal possible resection prior to radiation therapy and chemotherapy.
In the adult CNS literature the extent of surgical resection appears to be an important prognostic factor. The CHOP/HUP study is an important and timely study that evaluates the issue extent of surgical resection in the pediatric population. This is one of the largest series completed in MRI era and it indicates that the extent of resection is an extremely important prognostic indictors in the pediatric population. A lively discussion ensued during the presentation of this data regarding the definition of gross total resection. Again emphasizing the arbitrary nature of this definition and the need for a more rigid definition allowing for easier comparisons across institutions.
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