Endoscopic diagnosis of gastric and oesophageal cancer in Lusaka, Zambia: a retrospective analysis.

INTRODUCTION: There are uncertainties surrounding the spectrum of upper gastrointestinal (UGI) diseases in sub-Saharan Africa. This is mainly due to the limitations of data collection and recording. We previously reported an audit of UGI endoscopic diagnoses in Zambia spanning from 1977 to 2014. We now have extended this analysis to include subsequent years, in order to provide a more comprehensive picture of how the diagnoses have evolved over 4 decades. METHODS: We combined data collected from the endoscopy unit at the University Teaching Hospital (UTH) in Lusaka during a previous review with that collected from the beginning of 2015 to the end of 2021. Since 2015, an electronic data base of endoscopy reports at the UTH was kept. The electronic data base was composed of drop-down menus that allowed for standardised reporting of findings. Collected data were coded by two experienced endoscopists and analysed. RESULTS: In total, the analysis included 25,849 endoscopic records covering 43 years. The number of endoscopic procedures performed per year increased drastically in 2010. With the exception of the last 2 years, the proportion of normal endoscopies also increased during the time under review. In total, the number of gastric cancer (GC) cases was 658 (3%) while that of oesophageal cancer (OC) was 1168 (5%). The number of GC and OC diagnoses increased significantly over the period under review, (p < 0.001 for both). For OC the increase remained significant when analysed as a percentage of all procedures performed (p < 0.001). Gastric ulcers (GU) were diagnosed in 2095 (8%) cases, duodenal ulcers (DU) in 2276 (9%) cases and 239 (1%) had both ulcer types. DU diagnosis showed a significantly decreasing trend over each decade (p < 0.001) while GU followed an increasing trend (p < 0.001). CONCLUSIONS: UGI endoscopic findings in Lusaka, Zambia, have evolved over the past four decades with a significant increase of OC and GU diagnoses. Reasons for these observations are yet to be established.

Association between oesophageal cancer and biomass smoke exposure: a case-control study.

Most African populations are regularly exposed to biomass smoke, but knowledge of associated health implications is limited. This study aimed to investigate the association between oesophageal cancer (OC) and exposure to biomass smoke. This case-control study was conducted in Lusaka, Zambia. Cases were patients with endoscopically diagnosed OC, while controls were healthy volunteers. Questionnaires were used to collect lifestyle risk factors. Two sets of data were analysed; one with unmatched cases and controls and the other one with matching by age and sex. We enrolled 366 patients (131 cases and 235 controls). Among the cases, 50 (38%) were female and the median age was 56 years (IQR = 46-65 years). OC was significantly associated with domestic exposure to biomass smoke in univariate analysis (OR: 3.1; 95% CI: 1.7-5.6, p < 0.001) and after adjusting for potential confounders (OR: 2.1; 95% CI: 1.1-3.8, p = 0.017). Matched comparisons showed similar results for this association in univariate analysis (OR: 2.9; 95% CI: 1.5-5.8, p < 0.001) and using conditional logistic regression (OR: 2.8; 95% CI: 1.3-5.9, p = 0.005). Other risk factors found to be associated with OC were rural residence (OR: 2.3; 95% CI: 1.0-5.3, p = 0.004), lack of formal education (OR: 3.9; 95% CI: 1.5-9.9, p = 0.04) and living in poor housing (OR: 2.4; 95% CI: 1.1-5.6, p = 0.034). In conclusion, there is an association between OC and domestic exposure to biomass smoke and other lifestyle factors linked to low socio-economic status.