Epidemiology and Treatment Outcome of Lymphomas in Children: A Study From a Developing Area in Cameroon

Abstract

Background: Lymphoma makes up about 12% of all childhood malignancies and it is the third most frequent cancer, after leukemia and brain tumors, in developed countries. When treated appropriately, cure rates exceed 90% for Hodgkin lymphoma (HL) and over 80% for non-Hodgkin lymphoma (NHL). However, there is scarcity of data on pediatric lymphomas in Cameroon and several other African countries. Aim: The aim of this study was to describe the epidemiologic pattern and assess the treatment outcome of lymphoma in children at the Mother and Child Centre (MCC), which is the sole pediatric oncologic treatment center in Cameroon. Methods: A retrospective review of medical records from January 2008 to December 2015 was conducted in all cases admitted into the MCC with a diagnosis of lymphoma. Data were analyzed using Epi Info 7 software. Survival analysis was performed using the Kaplan-Meier methods. P value < 0.05 were used to declare statistical association. Results: Of the 1080 files studied, lymphoma was the most common childhood cancer, representing 36% of all (390 of 1080 cases studied). There was a decrease annual incidence of pediatric lymphoma from 2.2 to 1.0 per 1000 children. The age at presentation ranged between 2 and 15 years, with a mean age of 10.7±3.3 years for HL and 8.5±3.4 for NHL. Males were more frequently affected, sex ratio: 1.7:1. Of the 390 cases, 362 (93%) were NHL while 28 (7%) were HL. The most common histopathologic subtype was nodular sclerosis (76%) for HL and Burkitt lymphoma for NHL (72%). The cervico-maxillary region was the most common tumor localization (54%). Nodal involvement (70%) was more predominant than extra nodal (30%). Most patients (79%) presented at advanced stages of the disease (stage III/IV). The treatment protocol used was the GFAOP (Groupe Franco-Africain d'Oncologie Pédiatrique) with median duration of 4 months (range 1-38 months). The five-year overall survival rate for HL was 74% and 51% for NHL. The stage of disease had a significant association with the overall survival ( P = 0.002). Conclusion: This study revealed a decreased annual incidence of pediatric lymphomas in Cameroon over the 8-year study period. Males were more susceptible and most patients present at the advanced stage of the disease. The treatment outcome of Hodgkin lymphoma is better than non-Hodgkin lymphoma, however, remains low when compared with high survival rates in developed countries.