- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
- Department of Neurosurgery, Aga Khan University Medical College, Karachi, Pakistan
- Department of Neurosurgery, Aga Khan University, Karachi, Pakistan
Muhib A. Khan
Department of Neurosurgery, Aga Khan University, Karachi, Pakistan
DOI:10.4103/2152-7806.99936Copyright: © 2012 Khan MA. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
How to cite this article: Khan MA, Godil SS, Tabani H, Panju SA, Enam SA. Clinical review of pediatric pilocytic astrocytomas treated at a tertiary care hospital in Pakistan. Surg Neurol Int 21-Aug-2012;3:90
How to cite this URL: Khan MA, Godil SS, Tabani H, Panju SA, Enam SA. Clinical review of pediatric pilocytic astrocytomas treated at a tertiary care hospital in Pakistan. Surg Neurol Int 21-Aug-2012;3:90. Available from: http://sni.wpengine.com/surgicalint_articles/clinical-review-of-pediatric-pilocytic-astrocytomas-treated-at-a-tertiary-care-hospital-in-pakistan/
Background:Pilocytic Astrocytoma (PA) is a common type of brain tumor in the pediatric population. They have a fairly good prognosis. This study describes PAs in detail, with a focus on the demographic factors, presenting features, management and prognosis, and aims, to identify the negative outcome predictors in our population, which can affect the course of the disease. This article will add to the understanding of PAs from a third world perspective.
Methods:The Aga Khan University medical records (1995 – 2007) were reviewed, to study the clinical features, management, and outcome of patients (0 – 15 years) with Pilocytic Astrocytomas (PAs) in our population. After a thorough review of the medical records, all the PAs diagnosed on the basis of histopathology at our Pathology Laboratory, during this period, were included in the study.
Results:Twenty-two patients were included with a mean age of 9.25 years. Male-to-female ratio was 1 : 1. The most common presenting feature was a sign of increased intracranial pressure. The most common location was the cerebellum followed by the cerebrum. Fifteen patients underwent maximum surgical resection. Three had recurrence, despite no residual tumor. There were 10 Intensive Care Unit (ICU) admissions and one inpatient mortality. Fifteen patients followed up in the clinic: Eight had recurrence and four underwent repeat surgery (three showed clinical improvement). Hydrocephalus was a predictor of ICU admission. Solid consistency was found to be a marker of recurrence.
Conclusion:Pilocytic Astrocytomas are the most common pediatric brain tumors in our population, commonly located in the cerebellum. Complete resection is the best treatment option, but some tumors are aggressive and recurrence is not uncommon. The possible negative outcome predictors are age, source of admission, extent of resection, hydrocephalus, and solid consistency.
Keywords: Pediatric brain tumors, pilocytic astrocytomas, prognostic factors
Pilocytic Astrocytoma (PA) is a common type of brain tumor in the pediatric population. PAs comprise of 19.1% of all pediatric brain tumors in the age group 0 – 14 years,[
This was a retrospective cross-sectional study. The Aga Khan University Hospital (AKUH) medical records were reviewed for a twelve-year period (1995 – 2007), after approval from the Ethical Review Committee of the AKUH, to identify pediatric brain tumor patients. The pediatric population was defined as patients aged below 15 years at the time of admission in our hospital. The patients were referred to our institution by various physicians in the community. As AKUH is one of the few centers in Pakistan operating on pediatric brain tumors, our referral catchment area was countrywide. After a thorough review of the medical records, all PAs diagnosed on the basis of histopathology at our Pathology Laboratory, during this period, were included in the study. Data was collected using a proforma on the following variables: age, gender, source of admission (Emergency Room or Consulting Clinic), presenting symptoms, radiological findings, tumor location, surgical management, adjuvant therapy (radiotherapy and chemotherapy), ICU admission, Inpatient mortality, neurological condition on discharge, duration of follow-up, neurological condition on follow-up in the clinic, recurrence, repeat surgery for recurrence, and late mortality. The association between the patient characteristics of age, gender, source of admission, hydrocephalus, and consistency, with the outcomes of ICU admission, recurrence, and repeat surgery were tested using Fisher's exact tests. On account of the small sample sizes, multivariate modeling was not possible. P-values less than 0.05 were considered significant. All analyses were done using the SAS version 9.2.
During the 12-year period of 1995 – 2007, 102 pediatric brain tumors were operated and 22 (21.6%) patients were diagnosed with Pilocytic Astrocytoma, based on the histopathology.
The mean age of the patients was 9.25 years, with most of the patients presenting in the adolescent age group of 10 to 15 years [
Presenting clinical and radiological features
Most of the patients (81.8%) presented with a Glasgow Coma Scale (GCS) of 15 / 15. Only one patient had a GCS of 3 and one had a GCS of 7. All the patients presented with more than one clinical sign, with signs of increased intracranial pressure (86.4%) being the most common, followed by focal neurological signs (52.9%) [
A majority of our patients were diagnosed radiologically on the basis of magnetic resonance imaging (MRI). The MRI was used as a single diagnostic modality in 12 (54.5%) patients, while computed tomography (CT) was used in three (13.6%) patients, but seven (31.8%) patients underwent both CT and MRI. Hydrocephalus was seen in nine (40.9%) cases. A cystic component was present in nine (40.9%) cases, while the remaining 13 (59.1%) were of solid consistency. A total of six (27.3%) cases showed contrast enhancement.
Location of tumors
Pilocytic Astrocytomas showed a predilection for the cerebellum; 11 (50%) were found in the cerebellum, eight (36.4%) in the cerebrum, two (9.1%) in brainstem, and one (4.5%) in the basal ganglia [
Surgical resection remained the mainstay of treatment, as all our patients underwent craniotomy, mostly for resection, with only two undergoing a biopsy. Out of these two patients, one died during the hospital stay and the other one did not show any clinical improvement (CI) on discharge.
Complete resection was attempted in 15 (68.2%) patients. Postoperative imaging was done in 10 of these patients; there was no residual tumor seen in seven of them, but three of the patients had a residual tumor. Even after no evidence of residual tumor in postoperative imaging, three patients had recurrence; one was given radiotherapy after repeat surgery, while one was treated with chemotherapy without any repeat surgery. The former showed clinical improvement, but the latter did not. Of the five (22.7%) patients who underwent partial resection, one was treated with postoperative radiotherapy, and one had late mortality, after 8.4 years, during the initial postoperative course of repeat craniotomy, due to recurrence of tumor. An extraventricular drain (EVD) was placed in seven patients before craniotomy, with two of them needing a ventriculoperitoneal shunt (VPS) later on. VPS alone was placed in three patients.
Ten (45%) patients were admitted in the Intensive Care Unit (ICU) and one (4.5%) patient died during the hospital course. This patient underwent biopsy of a tumor in the cerebrum. Most of the patients, 20 (90.9%), had neurological improvement on discharge. Out of 22, 15 (68.2%) patients came for follow-up visits in the clinic and 11 (73.3%) showed progressive neurological improvement. The follow-up time period ranged from three months to 12 years, with a mean follow-up period of 3.72 years [
Predictors of negative outcome
A number of factors (e.g., age, source of admission, gender, location of tumor, cystic component, contrast enhancement, hydrocephalus, and extent of resection) were considered, which could affect the postoperative course, functional status, and prognosis of the patients [
Pilocytic Astrocytomas were found to be the most common pediatric brain tumors (21.6%) in our study population, which was comparable to the CBTRUS,[
Pilocytic Astrocytomas could arise in various locations in the neuroaxis, such as, the optic nerve, optic chiasm, hypothalamus, cerebellum, brain stem, thalamus, basal ganglia, and cerebral hemispheres. In our study, they showed a predilection toward the posterior fossa, particularly the cerebellum (50%). Aarsen et al.[
There exists a subset of patients who have an aggressive clinical course and require multiple resections or other therapies to control tumor growth.[
Out of the total, 15 patients came for follow-up in clinics. Only one late mortality was seen after 8.4 years, although eight patients had recurrence, and four underwent repeat surgery. Those patients who underwent repeat surgery showed clinical improvement, while others did not. It was found in a study conducted, in 2001, that repeat surgery for tumors located in the cerebral hemispheres or cerebellum resulted in gross total resection or near total resection in all cases and resulted in long periods of progression-free survival, without further adjuvant treatment.[
Due to variations in the prognosis of all the patients, we tried to find out the predictors of negative outcomes. Previous studies have identified several risk factors for tumor recurrence / progression including, age, site, and extent of resection, although several of these remain controversial.[
Aarsen et al.[
Pilocytic Astrocytomas are the most common pediatric brain tumors in our population and are most commonly located in the cerebellum. Complete surgical resection is the best treatment option for PAs. However, some tumors follow an aggressive course and recurrence is not uncommon. A second surgical resection after recurrence has a likelihood of better prognosis. The negative outcome predictors, according to our study, are age, source of admission, extent of resection, solid consistency, and hydrocephalus. As the number of cases in our study is small, there is a need to do a larger study, with more cases of PAs in the Pakistani population, to determine if there are any ethnic differences in the epidemiology, prognostic factors, and outcomes, as compared to other studies from different parts of the world.
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