Pediatric Brain Tumours at a Tertiary Care Hospital in Karachi

Abstract

The objectives of this study were to determine the epidemiology of brain tumors during infancy and childhoodand to define and segregate childhood brain tumors vis-à-vis their morphological characteristics. The presentstudy includes pediatric brain tumors, ICD-10 category C71 encountered during 10 years (January 1989 throughDecember 1998) at a tertiary care hospital in Karachi. Eighty one cases were included, 58 (71.6%) in males and23 (28.4%) in females with a male to female ratio of 2.5:1. The cases were divided into 3 age groups eachcovering five years of life (0-4, 5-9, 10-14 years), with the greatest number in the second age group i.e. 5-9 yearsfollowed by the third age group and the 0-4 year age group. The mean age for all cases, both genders was 8.8years (95% CI 7.9; 9.6) with a marginal variation for cases occurring in the cerebrum and cerebellum. Themalignancies occurred at a younger age in the males for each subcategory by site and morphology. Themorphological distribution of cases was astrocytoma (28 cases, 34.6%), primitive neuroectodermal tumor orPNET (40 cases; 49.4%), ependymoma (8 cases, 10%), mixed glioma (4 cases; 5%) and a case ofoligodendroglioma. The 81 malignancies included in this study were further categorized by site into two groups,supratentorial (27 cases; 33.3%) and infratentorial (54 cases; 66.7%). The morphological categorization ofsupratentorial tumors was astrocytoma (17 cases; 63%), ependymoma (5 cases; 18.5%), mixed glioma (2 cases;7.4%). PNET with rhabdoid differentiation, oligodendroglioma and pinealoblastoma comprised 1 case (3.7%)each. The 17 supratentorial astrocytoma were sub-categorized as follows - pilocytic astrocytoma (5 cases; 29.4%),grade II astrocytoma (6 cases; 35.3%); grade III astrocytoma (2 cases; 11.8%), anaplastic astrocytoma (1 case;5.9%) and glioblastoma multiforme (3 cases; 17.7%). The morphological categorization of infratentorial tumorswas astrocytoma (11 cases; 20.4%), medulloblastoma (38 cases; 70.4%), ependymoma (3 cases; 5.6%) and mixedglioma - astroependymoma (2 cases, 3.7%). The morphological sub-categorization of infratentorial astrocytomawas pilocytic astrocytoma (7 cases, 63.6%), with gemistocytic astrocytoma, grade II, grade III and anaplasticastrocytoma comprising 1 (9.1%) case each. The morphological categorization of medulloblastoma was classicalmedulloblastoma (15 cases; 39.5%), desmoplastic medulloblastoma (8 cases; 21.1%), medulloblastoma withastrocytic differentiation (12 cases; 31.5%), medulloblastoma with neural differentiation (2 cases; 5.3%), andneuroblastic medulloblastoma (1 case; 2.6%). The pediatric brain tumors in Karachi reflect a developing countryscenario, with a strong male predisposition and a late presentation with a peak in the 5-9 year age group. Thereis a predominance of medulloblastoma and a paucity of astrocytomas. The current study is a single institutionstudy and needs cautious interpretation. Population-based studies are required to determine the cancer burdendue to pediatric malignancies of the brain in this population and for the morphological categorization of braintumors in Karachi.