Pattern of brain tumours in Kenyatta National Hospital: a 3 year cross-sectional study.

Abstract

Background The burden of brain tumours in Kenya is still largely unknown though information from the Nairobi Cancer Registry suggests that they form about 2.3% of all reported male cancers and 0.9% of all female cancers. Kenyatta National Hospital (KNH) remains the main centre for neurosurgery in Kenya and as a result, the majority of patients with brain tumours continue to present at the hospital. Objective To describe the characteristics of brain tumours including clinical presentation, radiological and histological patterns in patients aged 13 years and more presenting at the Kenyatta National Hospital over a period of three years from January 2012 to December 2014. Study methods and design This was a 3-year hospital-based descriptive cross-sectional study. The study was conducted at Kenyatta National Hospital amongst patients aged 13 years and above with brain tumours that underwent surgery confirmed by histology from January 2012 to December 2014. The clinical syndromes, radiological features and histological types were described. The prevalence rates of the different brain tumours were given and tests of association (chi-square or Fischer’s exact test) where possible were performed to explore the relationship between the three features. Significant associations were explored further using logistic regression. Results It was found that there was an overall mean age of 40.63 yrs for all brain tumours with a range of 13-70 years. Peak was at 40 years. Overall male to female ratio was 1:1.49. Main occupations seen with brain tumours were farmers and housewives. Kikuyu ethnic group were seen more at 53.29%. Headache and visual deficits were the chief complaints at presentation. Familial history of brain tumours only occurred in 2.63% of our patients. Most patients operated on had a good performance score with GCS of 15/15. Most of the tumours seen were supratentorial. Only 1.31% of brain tumours presenting in our setup had any familial associations. Meningiomas at 41.4% and gliomas at 26.3% were the most common tumours seen. Glioblastoma accounted for 55% of all gliomas seen. Male to female ratio for meningiomas was 1: 3.2 with a mean age of 43.97 years. Gliomas had a male to female ratio of 1.35: 1 with an average age of 39.65 years. Most meningiomas were located in the sphenoid wing and convexity locations while most gliomas were frontal and temporal. Conclusion It was found that we are seeing brain tumours at a younger age at KNH compared to the average age of brain tumour presentation in the western world with most studies quoting an average age of above 59 years with glioblastomas and meningiomas having an average of 64 and 65 years respectively. Females are presenting more commonly with meningiomas while males are presenting more commonly with gliomas. Ethnic and geographic variables are a key determinant to access to neurosurgical care in our local setup. Headache and visual deficits are a key indicator of presence of brain tumour. A lower proportion of brain tumours with familial associations are been seen in KNH when compared to averages from western studies at 5%. Most of the tumours seen in the adult population are supratentorial. Meningiomas and gliomas are the commonest tumours seen in our set up accounting for 67.7% of all brain tumours. Glioblastoma are still the commonest gliomas seen and carry a grave prognosis. Gliomas occur in a younger age group compared to meningiomas. More metastatic tumours are been offered surgical care compared to previous studies done in KNH. Supratentorial tumours are the commonest tumours in adults. Proximity to neurosurgical care and the socioeconomic status has a bearing on access to neurosurgical services. Many of the neurosurgical patients from far flung areas away from Nairobi county where KNH is located are been seen in Eldoret referral hospital or are not getting proper neurosurgical services due to under diagnosis and lack of specialist services. Recommendations More vigilance needed in our local setup as patients are presenting with brain tumours at a much younger age. The patients to be empowered economically so that they can be able to access neurosurgical care promptly which has a direct effect on outcomes and prognosis. Neurosurgical services need to be decentralized too.