Geographic Variation of Incidence Rates of Cancer and Associated Risk Factors in Northern West Bank, Palestine (2005-2008)

Faten Tanjeer
Jihad M. Abdallah

Background: Cancer is the third leading cause of deaths in the Occupied Palestinian Territories accounting forabout 10% of total deaths. Despite its importance, little research has been devoted to characterization of incidencerates and geographic variations. Differences in risk factors, socioeconomic status and access to medical services arepossible reasons for the geographic variations in incidence rates. This study compared the incidence rates and somerisk factors of cancer among the six governorates of Northern West Bank and among types of locality (classified asurban, rural, and refugee camps) for the period 2005-2008.Methods: Crude and age-adjusted incidence rates (and 95% CI) were calculated using cancer data obtained from theregistry files of three hospitals in Northern West Bank. Negative binomial regression analysis was performed tocompare incidence rate ratios (IRR) among governorates and types of locality while adjusting for age-group, sex,and year of diagnosis. Fisher’s exact test was also employed to test for relationships among cross tabulatedvariables.Results: The lowest overall incidence rate was found in the governorate of Jenin (age-adjusted rate of 45.0 cases per100,000 over the 4-yr period). With Jenin taken as a reference, the governorate of Nablus had the highest incidencerate ratio (3.30) with age-adjusted incidence of 148.1 cases per 100,000. Refugee camps had higher overallincidence rate than urban and rural areas (age adjusted rates of 169.0, 103.2, and 79.3 cases per 100,000 for refugeecamps, urban areas, and rural areas, respectively). Geographical differences were found in the distribution ofpatients with regard to types of environmental pollution, smoking and alcohol consumption, types of stress, andchronic diseases.Conclusion: In Northern West Bank, large differences were found among areas of residence (governorates andlocality types) in incidence of cancer. Geographical differences in risk factors were also found which could explainpart of the geographic differences observed in incidence rates.