Changing Incidence of Uterine Cancer in Rural Egypt: Possible Impact of Nutritional and Epidemiologic Transitions

Uterine cancer is a top-ranking women's cancer worldwide, with wide incidence variations across countries and by rural and urban areas. Hormonal exposures and access to health care vary between rural and urban areas, globally. Egypt has an overall low incidence of uterine cancer but variable rural and urban lifestyles. Are there changes in the incidence of uterine cancer in rural and urban areas in middle-income countries such as Egypt? No previous studies have addressed this question from a well-characterized and validated population-based cancer registry resource in middle-income countries. The aim of this study was to explore the differences in clinical and demographic characteristics of uterine cancer over the period of 1999 to 2010 in rural and urban Gharbiah province, Egypt.

Data were abstracted for all 660 patients with uterine cancer included in the Gharbiah Population-based Cancer Registry. Clinical variables included tumor location, histopathologic diagnosis, stage, grade, and treatment. Demographic variables included age, rural or urban residence, parity, and occupation. Crude and age-adjusted incidence rates (IRs) and rate ratios by rural or urban residence were calculated.

No significant differences were observed in most clinical and demographic characteristics between rural and urban patients. The age standardized IR (ASR) was 2.5 times higher in urban than in rural areas (6.9 and 2.8 per 100,000 in urban and rural areas, respectively). The rate ratio showed that the IR in urban areas was 2.46 times the rate in rural areas.

This study showed that the disease IR in rural areas has increased in the past decade but is still low compared with the incidence in urban areas in Egypt, which did not show a significant increase in incidence. Nutritional transitions, obesity, and epidemiologic and lifestyle changes toward Westernization may have led to IRs increasing more in rural than in urban areas in Egypt. This pattern of increasing incidence in Egypt, which used to have a low incidence of uterine cancer, may appear in other middle-income countries that experience emerging nutritional and epidemiologic transitions. The rate of uterine cancer in urban areas in Gharbiah is almost similar to the corresponding rates globally. However, the rate in rural areas in this population has increased over the past decade but is still lower than the corresponding global rates. Future studies should examine the etiologic factors related to increasing rates in rural areas and quantify the improvement in rural case finding.