Stacey Fedewa

Geographical Patterns of Bladder Cancer in Egypt's Gharbiah Governate

BACKGROUND: Bladder cancer is the most common malignancy in Egyptian males representing 16% of male cancer cases. Historically, high rates of bladder cancer in Egypt have been attributed to schitosomiasis infection which is an established cause of squamous cell carcinoma (SCC). In recent years, SCC has declined with schitosomiasis control; however; an increase in transitional cell carcinoma (TCC) have caused bladder cancer incidence to remain steady. With these changing patterns, additional risk factors for bladder cancer in Egypt need to be explored. This study describes the geographical patterns of bladder cancer in Gharbiah Governate as a first step in exploring these factors. The Gharbiah Governate is located in the Nile Delta Region containing agriculture, textile, and pesticide industries.

METHODS: Registry data on smoking, community of residence, age, sex, tumor grade, stage, and morphology was collected on 1209 bladder cancer cases diagnosed between 1999 and 2002 from Gharbiah Population Based Cancer Registry. Expected versus observed incidence, age-adjusted incidence rates were calculated for males, females, and total population for each of the 8 administrative districts and the 316 communities in Gharbiah. Age adjusted sex specific cluster analysis using SATSCAN software was completed to determine spatial patterns at the community level.

RESULTS: Higher than expected rates and elevated incidence rates of bladder cancer were identified in the district of Kotour (IR=17.01 per 100,000 person years). This rate is higher than the average incidence rate in the Gharbiah governate (IR=8.29 per 100,000 person years).The capital of Kotour, Kotour City had the highest bladder cancer incidence among the 316 communities (IR= males 134.30 per 100,000 PY 73.106 per 100,000 PY). Cluster analyses results indicate clustering around Kotour City.

CONCLUSIONS: Future studies environmental risk factors in relation to the spatial patterns of bladder cancer in this region need to be conducted; particularly in the Kotour District.

Incidence analyses of bladder cancer in the Nile delta region of Egypt