CHAPTER ONE

INTRODUCTION

1.1 Background

            Cancer is a disease in which abnormal cells grow uncontrollably, disregarding the rules of cell division and can spread to surrounding body tissue.[1]The National Cancer Institute of the United States defines paediatric cancers as “cancers that occur between birth and 15 years of age”[2]. Cancer is the leading cause of death in children and adolescents around the world and each year ~429,000 children and adolescents aged 0 to 19 years are expected to develop cancer[3].Estimates show that there will be 13·7 million new cases of childhood cancer globally between 2020 and 2050 with 11·1 million deaths of children from cancer if no additional investments are made to improve access to health-care services or childhood cancer treatment[4].

            The most common categories of childhood cancers worldwide include leukemias, lymphomas, brain cancers, and solid tumours, such as neuroblastoma, retinoblastoma and renal tumours, the first being Wilms tumour[5]. Internationally, a great variation in childhood cancer incidence and outcomes occurs when comparing high-income countries to low-income ones[6].The overwhelming majority of cases of cancer in children and adolescents occur in low-income and middle-income countries, which bears a larger part of the global cancer burden for this age group[7].Such differences may be due to genetic predisposition, being able to diagnose cancer, early or delayed exposure to infectious diseases, and other environmental factors[6].  Childhood cancers are more prevalent in sub-Saharan Africa than in high-income countries: in sub-Saharan Africa, paediatric cancers account for 4.6% of all cancers in comparison to 0.5% in high-income countries[8].In developed countries, childhood cancer has a mortality of approximately 20% of cases while in low income countries, mortality is approximately 94%[9]. The WHO Global Initiative for Childhood Cancer was launched with the aim increasing child cancer survival rates to at least 60% and alleviating suffering of all children by 2030 withtwo main objectives which are to Increase the capacity of countries to deliver quality services for children with cancer and to Increase the prioritization of childhood cancer at global, regional and national levels[10].In Cameroon, over the past ten years, the attention of the public health sector has shifted towards the treatment and prevention of cancer, however, the true epidemiological burden of cancer is relatively unknown and there is little data available[11].The CameroonianNational Committee for the Fight against Cancer (NACFaC) determined that the most prevalent cancer in childhood in the country is Burkitt’s lymphoma. The Ministry of Public Health launched the cancer control strategy for 2020 to 2024. The general objective of this Plan is to reduce by 10%, the cancer related morbidity and mortality by 2024, and attenuate its socio-economic impact on the development of the country. It also contains specific activities for improving survival for childhood cancer[12]. The results of a study titled “the epidemiology of paediatric cancer in the north west region of Cameroon” showed that the incidence of paediatric cancer originating from the Northwest Region of Cameroon is 5.92 cases (95% CI: 4.79 – 7.05) per 100,000 persons per year[13]. In 2008 cancer registration was set up Banso Baptist Hospitaland Mbingo Baptist Hospital in the Northwest region of Cameroon, using the Pediatric Oncology Networked Database (POND). The objective of this study was to analyze the POND registry data for patients with cancer aged 0–15 years for the period 2004–15. A total of 1029 malignancies were recorded in children 0–15 years in the study period. The male-to-female ratio was 1.4:1. The median age at diagnosis was 7.22 years. The most common malignancies were lymphomas followed by nephroblastoma, retinoblastoma, rhabdomyosarcoma and Kaposi sarcoma[14]. Reasons reported for poor survival in pediatric malignancies are poor or delayed follow up of patients i.e. patients delay in coming for their appointments after beginning of treatment[15], delay in first consultation at oncologic centers leading to diagnosis at a late stage [16].

1.2 Problem Statement

            In sub-Saharan Africa, the incidence paediatric cancers are higher as compared to high income countries. In developed countries, childhood cancer has a mortality of approximately 20% of cases while in low income countries, mortality is approximately 80%, or even 90% in the world’s poorest countries.A study was carried out in 2018 on the epidemiology of paediatric cancers in the North West region of Cameroon but the characteristics (clinical, paraclinical) and the factors associated with mortality in patients with malignancies were not explored. The reasons for poor survival have been reported in another study but not in the North West region. It is therefore necessary to study thecharacteristics and the factors associated with mortality in patients with paediatric malignancies.

1.3 Rationale/ Justification

            This study will provide knowledge on the clinical, paraclinical characteristics of paediatric malignancies, and the factors associated with mortality in patients with these malignancies. The results of this study may suggest measures that will help decrease mortality and increase quality of life in children with malignancies.

1.4 Research Questions

            In order to determine the characteristics and to identify the factors associated with mortality of patients in the paediatric oncology unit of Mbingo Baptist Hospital, we were guided by the following research questions.

• What are the different types and stages of malignancies in the Mbingo Baptist Hospital?
• What are the treatment protocols received by the patients and what complications developed
• What are theoutcomes of patients with these malignancies?
• What factors are associated with mortality in these patients?

1.5 Research Hypothesis

            Null hypothesis: The characteristics and factors associated with mortality in paediatric malignancies at Mbingo Baptist Hospital from 1^st January 2017 to 31^st December 2019, cannot be ascertained

            Alternate hypothesis: The characteristics and factors associated with mortality in paediatric malignancies at Mbingo Baptist Hospital from 1^st January 2017to 31^st December 2019, can be ascertained

1.6 Research Objectives

1.6.1. General Objective

            To determine thecharacteristics and to identify the factors associated with mortality of patients with malignancies in theMbingo Baptist Hospital.

1.6.2  Specific Objectives

• To list the different types and stages of paediatric malignancies in the MBH
• To describe the treatment received and any complications developed
• To determine the outcome of patients with these malignancies
• To identify the factors associated with mortality in these patients