Risk factors associated with oesophageal cancer in Bulawayo, Zimbabwe

Abstract

SununrThis report presents information on n'sk factors for oesophageal cancer in Bulawayo. Zimbabwe. The data analysed were from the Cancer Registry of Bulawayo for the years . when all registered patients were interviewed using a standard questionnaire. The age-standardised incidence rates in the urban population of Bulawayo in the first 10 year period were 58.6 per 100 000 in men and 8.1 in women. The distribution of risk factors was assessed in 881 oesophageal cancer cases (826 male. 55 female) and a control group comprising other non-tobacco-and non-alcohol-related cancer (5238) Cancer of the oesophagus varies widely in incidence between different parts of the world. One area of high risk is in southern and eastern Africa, where it constitutes 11.5% of cancers in men, corresponding to an annual age-standardised incidence rate of 20.7 10-5 . Previous reviews (Oettle. 1964: Cook, 1971) have drawn attention to the male excess (ranging from 1.5 to 12 in different series). and the apparent increase in incidence over time, with hospital series from the 1930s and 1940s suggesting that it was at that time a relatively rare condition. Within east and southern Africa, areas of high and low incidence are intermingled, and the sharp geographic gradients in nrsk suggest a predominant role for environmental carcinogens in the aetiology (Day and Mufioz. 1982).In al., 1970, 1976. 1993 Odds ratios (ORs) for each risk factor, with 95% confidence limits, were estimated. while controlling for potential confounding variables, by multivariate regression. using the GLIM software package (Baker and Nelder, 1978). Subjects with missing values for the variables studied were included in the analyses as a separate category. Individuals non-resident in Zimbabwe were excluded from the analysis. P-values for trend were calculated by categorising and scoring the exposure variable and treating it as continuous. ResultsNot all of the patients (or their relatives) could be interviewed, and in those who were, the questionnaire was not always completed. Overall, a complete interview was obtained in 72.6% of oesophageal cancer cases, and in 71.3% of the control group cancers.

Risk factors for oesophageal, lung, oral and laryngeal cancers in black South Africans

“…In contrast to several southern African studies from the 1960s and 1970s which failed to show this effect (e.g. Bradshaw and Schonland, 1974;Vizcaino et al, 1995), the current study agrees with the majority. Many earlier studies were conducted in areas where, and at times when, the principal beverages had a low (2 -4%) alcohol content possibly giving increased risks that were undetectable.…”

“…Previous case -control studies from South Africa Schonland, 1969, 1974;van Rensburg et al, 1985;Sammon, 1992) and Zimbabwe (Vizcaino et al, 1995) showed an elevated risk for the development of oesophageal cancer with tobacco smoking; and various international (Tuyns et al, 1979;Day, 1984) and local (McGlashan et al, 1982) studies, the most recent by Segal et al (1988), have suggested that alcohol and tobacco consumption have independent and combined risk effects for this cancer. The incidence of oesophageal cancer has been increasing in South Africa since the 1950s (Segal et al, 1988), with the risk being much higher than the national average for those living in the Eastern Cape Province, particularly the rural areas of the former Transkei 'homeland' (Rose, 1973;Makaula et al, 1996) where nutritional factors and consumption of Fusarium sp contaminated maize may be important contributing factors (see Gelderblom et al, 1988).…”

Occupational exposures and risk of esophageal and gastric cardia cancers among male Swedish construction workers

“…In some occupational groups positive associations with esophageal cancer have previously been found, e.g. among workers in the rubber industry, automobile building industry workers, chimney sweeps, mine workers, individuals working with chemical products, medical X-ray workers, workers in the cement industry, plastics and composites industry workers, dye production industry workers, bookbinders, individuals with administrative jobs, health professionals, dry cleaning workers and asphalt workers [25][26][27][28][29][30][31][32][33][34][35][36][37][38]. Specific exposures and agents that have been linked with esophageal cancer include metal dust, asbestos, silica dust, combustion products, sulphuric acid, carbon black and organic solvents [39][40][41][42][43][44][45][46][47].…”

Systematic review: epidemiology of Oesophageal Cancer in SubSaharan Africa

“…In developing countries, it was the 5th commonest cancer 4 , while in Sub-Saharan Africa, 15,150 cases in males & 7,200 cases in females were estimated to occur in 2002 1,5 . It is interesting to note that other types of cancers common in the region are Kaposi's sarcoma and cancer of cervix 6,7 which are prioritized indirectly by provision of some resources towards them from well concerted efforts of the governments in the region together with development partners through global support against communicable diseases which are their aetiological factors, HIV/AIDS and HPV, respectively.…”