Occupations and Risk of Head and Neck Cancers: A Case-Control Study in Tanzania

Cancer is a major global health concern. Head and neck cancers are the sixth most prevalent type of cancer globally; it has been suggested that these cancers can be caused due to pesticide exposure during agricultural activities. In this study, we aimed to investigate whether agricultural labor is associated with an increased risk of head and neck cancers. A case-control study was performed in Ocean Road Cancer Institute in Tanzania: a national, specialized cancer hospital. A total of 298 head and neck cases and 305 controls were included. Occupational history and information about lifestyle factors and diet were obtained by interview. Using logistic regression analyses and adjusting for lifestyle and diet, an increased risk of head and neck cancer was found among workers with a history of agricultural work, with an odds ratio of 2.6 and a 95% confidence interval of 1.60-4.37. When including only non-smokers and non-alcohol users (n = 363), a similar estimate was found. Participants with over 10 years (n = 481) of agricultural work experience, after adjusting for lifestyle and diet, exhibited an odds ratio of 5.1, with a 95% confidence interval of 2.56-9.94. Our findings indicate that agricultural work is associated with the risk of head and neck cancer. Carcinogens in agriculture should be examined in future studies.