OESOPHAGEAL AND LUNG CANCERS IN NATAL AFRICAN MALES IN RELATION TO CERTAIN SOCIO-ECONOMIC FACTORS - AN ANALYSIS OF 484 INTERVIEWS

In view of the high incidence of oesophageal and lung cancer in African males of Durban, shown in Table I, an investigation of certain socio-economic factors has been undertaken. Interviews on 98 male African oesophageal cancer patients, 45 male African lung cancer patients and 341 male African patients not suffering from malignant disease were undertaken at a large Durban hospital. The method of the survey and the method of analysing the variables after adjusting for age differences in the three groups is outlined. The chi-square method was used. A number of variables showed no differences between the three groups, and those showing differences significant at the 2 % and 5 % level are shown in Table II. A number of other variables showed significant differences between the three groups (P < 0·01) and these fell into four main groups: (a) self administered medicines (Table III), (b) kinds of alcohol taken (Table III), (c) the use of tobacco (Table IV), (d) possible exposure to occupational carcinogens (Table VI). The findings on these groups of variables were as follows. (a) Although the two cancer groups used emetics and purgatives more frequently than the control group, it is possible that this finding was connected with the presence of a chronic illness, rather than with cancer causation. Nevertheless this survey indicates that native remedies are still frequently taken. The regular use of emetics represents a type of oesophageal insult. (b) The consumption of alcoholic concoctions was more frequent in both cancer groups than in the control group, with the lung cancer group drinking more concoctions than the oesophageal cancer group. (c) On considering the use of tobacco, it was found that both oesophageal and lung cancer groups had more tobacco users than the control group. Analysis of the type of tobacco used indicated that oesophageal cancer cases smoked pipes more than the other groups, and lung cancer cases smoked cigarettes more than the other groups. Both oesophageal and lung cancer groups had an excess of males who had smoked for over 30 years in comparison with the control group. Both cancer groups had a higher lifetime consumption of tobacco than the control group, and the oesophageal cancer group had the highest lifetime consumption. (d) It was found that both oesophageal and lung cancer groups had been exposed to more possible occupational carcinogens and for longer periods than the control group. An analysis of the possible carcinogens involved indicated that petrol, oil and tar were the commonest carcinogens associated with the lung cancer group, and asbestos and lead were most commonly associated with the oesophageal cancer group. The authors feel that the connection between smoking and lung cancer in African males has been established, in previous papers, and in this paper. It is suggested by the authors that a variety of oesophageal insults, including those which emerge from the study, taken in conjunction with a general state of malnutrition in African males, may combine to promote the development of oesophageal cancer. Connection with a specific carcinogen has yet to be established. © 1969, The British Empire Cancer Campaign for Research. All rights reserved.