Jennifer Schlichting

Comparison of Early- to Later-Onset Breast Cancer in the Gharbiah, Egypt and US SEER Population-Based Cancer Registries

Studies dating back over thirty years have reported a high proportion of “rapidly progressing breast cancer” (RPBC) with inflammatory breast cancer (IBC) characteristics in the North African country of Tunisia.(1-3) Findings from these Tunisian studies have spurred interest in further breast cancer (BC) research in the mid-East, and particularly in North Africa. Recent BC studies in the region have focused on Egypt, aided by the founding of the Gharbiah population-based cancer registry (GCR) in 1998 as part of the Middle East Cancer Consortium (MECC). (4) Although multiple studies have suggested there is an increased proportion and/or incidence of an earlier-onset BC type in North Africa as compared to other regions, and that earlier onset cancers may be of different etiology and carry different risk factor profiles than those occurring later in life, no studies have been located that examine early- vs. late-onset BCs in a population based cancer registry in a North African country. Therefore, this study proposes to compare sociodemographic and tumor characteristics between early- and later-onset BCs in the GCR as well as the US Surveillance, Epidemiology, and End Results (SEER) database over the same time period, which will allow for detection of differences in early- and later-onset individual and tumor characteristics between the two countries. Within and between country differences for early- and later-onset BCs may indicate different etiologies and risk factor profiles and have important implications for public health BC prevention efforts and clinical practice. 

Data sources for this study will include BC cases from 1999-2009 contained in the GCR in Tanta, Egypt, and the US SEER database. Variables available include: year of diagnosis, age at diagnosis, region of residence, estrogen and progesterone receptor status, tumor grade, stage, morphology, marital status, and laterality. In order to help determine at what age BC incidence rates peak in each country, age- and country-specific incidence rates will be calculated for 5-year age groups using Egyptian and US census data to obtain population denominators. Three logistic regression models, one for each of three age groups: <=40 years of age, 41-54 years of age, and >=55 years of age will be fit to examine the association within each age group between country of residence and tumor and sociodemographic characteristics.

1. Tabbane F, Muenz L, Jaziri M, Cammoun M, Belhassen S, Mourali N. Clinical and prognostic features of a rapidly progressing breast cancer in Tunisia. Cancer. 1977 Jul;40(1):376-82.
2. Mourali N, Muenz LR, Tabbane F, Belhassen S, Bahi J, Levine PH. Epidemiologic features of rapidly progressing breast cancer in Tunisia. Cancer. 1980 Dec 15;46(12):2741-6.
3. Costa J, Webber BL, Levine PH, Muenz L, O'Conor GT, Tabbane F, et al. Histopathological features of rapidly progressing breast carcinoma in Tunisia: A study of 94 cases. Int J Cancer. 1982 Jul 15;30(1):35-7.
4. Freedman LS, Edwards BK, Ries LAG, Al-Kayed S, Barchana M, Ibrahim AS, et al. Chapter 1: Overview and summary data. In: Freedman LS, Edwards BK, Ries LAG, Young JL, editors. Cancer Incidence in Four Member Countries (Cyprus, Egypt, Israel, and Jordan) of the Middle East Cancer Consortium (MECC) Compared With US SEER. NIH Publication No. 06-5873 ed. Bethesda, MD: National Cancer Institute; 2006. p. 1-27. 

Schlichting JA, Soliman AS, Schairer C, Banerjee M, Rozek LS, Schottenfeld D, Harford JB, Merajver SD. Association of Inflammatory and Non-Inflammatory Breast Cancer with Socioeconomic Characteristics in the Surveillance, Epidemiology, and End Results Database, 2000–2007. Cancer Epidemiol Biomarkers Prev. 2012 Jan;21(1):155-65. doi: 10.1158/1055-9965.EPI-11-0833. Epub 2011 Oct 25.

Schlichting JA, Soliman AS, Schairer C, Schottenfeld D, Merajver SD. Inflammatory and non-inflammatory breast cancer survival by socioeconomic position in the Surveillance, Epidemiology, and End Results database, 1990-2008. Breast Cancer Res Treat. 2012 Aug;134(3):1257-68. doi: 10.1007/s10549-012-2133-2. Epub 2012 Jun 26.


About Jennifer
Jennifer received her doctoral degree in the Department of Epidemiology from the University of Michigan School of Public Health in 2013. Her dissertation projects focus on inflammatory and early-onset breast cancer incidence and survival using the US SEER and Gharbiah, Egypt population-based cancer registries. The specific aims of her dissertation projects are to determine if differences exist in inflammatory breast cancer incidence and survival by geographic location of residence, socioeconomic position, and tumor characteristics in the US SEER registry, as well as to compare early onset breast cancers in the Gharbiah, Egypt cancer registry to those in the US SEER database. Prior to beginning the Epidemiology doctoral program at the University of Michigan, she was a Research Project Manager in the Diabetes Research & Training Center at the University of Chicago. Jennifer graduated with an M.S. in Epidemiology from the University of Illinois at Chicago in 2006 and a B.S. in Health Behavior & Education from the University of Illinois at Urbana-Champaign in 2002.