Geographic Distribution of Inflammatory Breast Cancer and Non-Inflammatory Breast Cancer in Gharbiah, Egypt

BACKGROUND: Inflammatory Breast Cancer (IBC) is a rare but aggressive form of breast cancer, constituting about 1-5% of breast cancers in the U.S. but about 11% in Egypt.The etiology of IBC is unknown, but the distribution of residence of IBC and non-IBC patients may provide clues to the disease risk factors.Therefore, we investigated the geographic distribution of IBC and non-IBC in the province of Gharbiah, Egypt.METHODS: All breast cancers diagnosed during the period of January 2009 to December 2010 were retrieved from the Gharbiah Population-based registry.IBC cases were obtained from a case-control study conducted in the same region and period.Incidence rates were calculated for IBC and non-IBC for each of the eight districts and their rural/urban regions. RESULTS:The incidence of IBC was higher in rural than urban areas, in contrast to the incidence of non-IBC.Clustering of IBC and non-IBC was observed more in urban than in rural areas.IBC clusters were detected in 7 of the 8 urban areas of Gharbiah, with the highest incidence identified in urban Kafr El-Zayat.Non-IBC clusters were distributed in all 8 urban areas of Gharbiah without clustering, with highest incidence is identified in urban Tanta. CONCLUSION:Our results showed different geospatial distributions of IBC and non-IBC relative to the regional environmental exposures.Future studies should explore specific environmental exposures that may contribute to the geographic distribution of IBC and non-IBC in the region to further explore the etiology of IBC and non-IBC.