Malignant tumours of childhood in Zaria

The increased prevalence of hitherto uncommon tumours in children in our geographic setting formed the basis for this study. This study aimed to determine the current histopathologic distribution pattern of paediatric malignancies in Zaria.

An eight year (2000-2007) consecutive analysis of malignant tumours in children ages 0 to 15 years in a referral University laboratory. All tissue biopsies were fixed in 10% formalin and processed in wax. Tumours were characterised histologically into tissues of origin and categorised into three age groups; <1 year, 1-5 years and 6-15 years.

189 children with malignant tumours were analysed. They showed a male preponderance (M: F; 1.2: 1.0) and their ages ranged from 5 days to 15 years. Tumours of mesenchymal origin were the commonest (115: 60.8%) while epithelial tumours including germ cell tumours accounted for 74 (39.2%) cases. The age group 1-5 years had the highest epithelial tumours while age group 6-15 years had the most tumours with 102 (54%) cases overall. The five commonest tumours over-all were rhabdomyosarcoma, Burkitt lymphoma, retinoblastoma, non-Hodgkin's lymphoma and nephroblastoma. Germ cell tumours affected the ovary predominantly and two of the endodermal sinus tumour cases were seen in the testis of an eighteen month child and sacrococcygeum of a 5 year old girl, respectively. Of the six immature teratoma cases, four were cutaneous in distribution. The vascular tumours included epithelioid haemangioendothelioma, haemangioblastoma and Dabska tumour and they accounted for (5.8%) of all tumours seen. The commonest sites of occurrence of these tumours were the oculo-orbital, jaw, head and neck regions with 82 cases (43.4%) while lymph nodes were involved in 31 (16.4%) cases.

The distribution and occurrence of malignant tumours in children is age related. Lymphomas were the commonest tumours overall while retinoblastoma and Burkitt lymphoma were the commonest tumours affecting children below 5 years and 6-10 years old, respectively, in our centre. The head region and lymph nodes were the sites of predilection for majority of these tumours.