The Spatial Distribution of Cancer Incidence in Fars Province: a GIS-Based Analysis of Cancer Registry Data
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Cleveland State University EngagedScholarship@CSU Civil and Environmental Engineering Faculty Publications Civil and Environmental Engineering 10-2013 The Spatial Distribution of Cancer Incidence in Fars Province: A GIS-Based Analysis of Cancer Registry Data Ali Goli Shiraz University Mahbobeh Oroei Shiraz University of Medical Sciences Mehdi Jalalpour Cleveland State University, [email protected] Hossein Faramarzi Shiraz University of Medical Sciences Mehrdad Askarian Shiraz University of Medical Sciences, [email protected] Follow this and additional works at: https://engagedscholarship.csuohio.edu/encee_facpub Part of the Biostatistics Commons, Civil Engineering Commons, and the Neoplasms Commons How does access to this work benefit ou?y Let us know! Original Citation Goli, A., Oroei, M., Jalalpour, M., Faramarzi, H., and Askarian, M. (2013). “The Spatial Distribution of Cancer Incidence in Fars Province : A GIS Based Analysis of Cancer Registry Data”, International journal of preventive medicine, 4(10), 1122–1130. This Article is brought to you for free and open access by the Civil and Environmental Engineering at EngagedScholarship@CSU. It has been accepted for inclusion in Civil and Environmental Engineering Faculty Publications by an authorized administrator of EngagedScholarship@CSU. For more information, please contact [email protected]. www.ijpm.inwww.ijpm.ir The Spatial Distribution of Cancer Incidence in Fars Province: A GIS‑Based Analysis of Cancer Registry Data Ali Goli, Mahbobeh Oroei1, Mehdi Jalalpour2, Hossein Faramarzi3, Mehrdad Askarian4 Department of Social Science, College of Human ABSTRACT Sciences, Shiraz University, Shiraz, Islamic Republic of Iran, 1Department of Community Medicine, Background: Cancer is a major health problem in the developing Student Research Center, Shiraz University of countries. Variations of its incidence rate among geographical Medical Sciences, Shiraz, Islamic Republic of Iran, 2Department of Civil Engineering, The Johns areas are due to various contributing factors. This study was Hopkins University, Maryland, United States of performed to assess the spatial patterns of cancer incidence in America, 3Department of Non-communicable the Fars Province, based on cancer registry data and to determine Diseases, Shiraz University of Medical Sciences, Shiraz, Islamic Republic of Iran, 4Department of geographical clusters. Community Medicine, Shiraz Nephro-Urology Methods: In this cross sectional study, the new cases of cancer Research Center, Shiraz University of Medical Sciences, Shiraz, Islamic Republic of Iran. were recorded from 2001 to 2009. Crude incidence rate was estimated based on age groups and sex in the counties of the Fars Correspondence to: Province. Age‑standardized incidence rates (ASR) per 100,000 Original Article Original Prof. Mehrdad Askarian, was calculated in each year. Spatial autocorrelation analysis was Department of Community Medicine, Shiraz University of Medical Sciences, performed in measuring the geographic patterns and clusters using P. O. Box: 71345-1737, Shiraz, Iran. geographic information system (GIS). Also, comparisons were E-mail: [email protected] made between ASRs in each county. Results: A total of 28,411 new cases were diagnosed with cancer Date of Submission: Oct 04, 2012 during 2001‑2009 in the Fars Province, 55.5% of which were Date of Acceptance: Jan 18, 2013 men. The average age was 61.6 ± 0.5 years. The highest ASR was observed in Shiraz, which is the largest county in Fars. The Moran’s How to cite this article: Goli A, Oroei M, Jalalpour Index of cancer was significantly clustered in 2004, 2005, and M, Faramarzi H, Askarian M. The spatial distribution of cancer incidence in fars province: A gis‑based analysis 2006 in total, men, and women. The type of spatial clustering was of cancer registry data. Int J Prev Med 2013;4:1122‑30. high‑high cluster, that to indicate from north‑west to south‑east of Fars Province. Conclusions: Analysis of the spatial distribution of cancer shows significant differences from year to year and between different areas. However, a clear spatial autocorrelation is observed, which can be of great interest and importance to researchers for future epidemiological studies, and to policymakers for applying preventive measures. Keywords: Cancer, Iran, spatial analysis INTRODUCTION Today, cancer is one of the most important health problems in the world, causing concerns for healthcare systems. Cancers cause high morbidity and mortality.[1,2] New cases of cancer are 1122 International Journal of Preventive Medicine, Vol 4, No 10, October, 2013 www.mui.ac.ir Goli, et al.: The mapping cancer in Fars province ever‑increasing worldwide, and more than half METHODS of the cases are from low and middle income This study was carried out in Fars Province, [3,4] countries. Increased exposure to a variety of which is located in southern Iran and has an area risk factors and social inequalities are expected to of about 122,400 km2 which is at 27°31’ to 31°42’ increase the absolute number of cancer cases and longitude north and 50°37, to 55°38’ latitude their consequences so that an increase of 35% of east.[22] The total population of Fars is about [3‑5] new cases is predicted in 2020. 4.6 million and male to female ratio is 1.03.[23] In developing countries, lack of equal access The administrative divisions in 2010 included to healthcare services and community status, 24 counties. The capital city is Shiraz, one of the adoption of western lifestyle, and increased old metropolises in Iran [Figure 1]. age have led that the burden of cancer has changed In this cross sectional study, we used map during recent decades, and Iran is not an exemption data, population distribution derived from census from these conditions.[6,7] and patient data. The new cases were patients Annually, almost 50,000 new cases occur in diagnosed with cancer whom are registered the Iranian population.[8] Cancer, is the third most between 2001 and 2009 among the study common cause of death in Iran after cardiovascular population in the Cancer Registry Center of Shiraz diseases and car accidents.[9‑12] It is estimated that University of Medical Sciences. This center use annually 35,000 deaths are due to cancer. Sadjadi multiple sources (hospital, diagnostic facilities, and et al., report that Iran is the second country based on death certification); the data were collected from mortality rate due to cancer in Eastern Mediterranean throughout the Province and then to be set up in region of world health organization (WHO).[6] Deputy of Health at Shiraz University of Medical In order to control and reduce morbidity and Sciences (Cancer Registry office). Also, these were mortality of cancer and also to carry epidemiological checked by the Ministry of Health, and then to be studies, geographical distribution of cancer should sent to this center in Shiraz. be determined as a first step.[12] Researchers have The reports were based on pathology demonstrated that a strong link exists between laboratories. Data sheet included 33,398 patient health status and areas where people live in.[1,8] names, sex, age at the time of diagnosis, place of The characteristics of an area such as, industrial residence, and cancer diagnosis that was based environment, climate, socioeconomic status, on the international classification of disease lifestyle, and racial groups have a strong effect on for oncology (ICD‑O).[24] The documents were cancer incidence and health outcomes.[1‑3,8,9] checked and any duplicates cases with the same Geographic information system (GIS) is a information, cases from the other provinces, unclear computer‑based system and a potentially powerful diagnosis, and uncertain address were excluded. assessment tool to represent health data in a visual The final data were summarized in another sheet format by linking statistical and thematic data and included 28,411 new cases and consisted of on maps. It can play a prominent role in helping sex, place of residence, types of cancers, and an public health authorities and policy makers for eight age‑group classification.[25] decision‑making and planning in epidemiological Crude incidence ratio was calculated for each studies.[13‑16] A review of published literature shows sex and age groups in counties in each year. Then, that many studies have been conducted on cancer to compare different counties, age‑standardized assessment by using GIS in countries.[1,2,17,18] rate (ASR) was calculated using standard world In Iran, most of existing literature in this context population.[26] is on epidemiological studies that have not used The calculated ASRs were transferred to the GIS spatiotemporal techniques.[9,11,12,19] Only a few software (Arc GIS 9.3), and mapping tools of GIS studies have documented evaluation of geographical were then used for visualizing ASR for each year.[27] variation of cancer incidence by applying GIS.[8,20,21] We also used exploratory spatial data This article aims to map the cancer incidence in analysis (ESDA) to determine distribution pattern the counties of Fars Province, and also to explore of cancer for each year of data.[28] One of the most the spatial pattern trends or changes of disease frequently used methods is Moran’s Index, which during the years 2001‑2009. evaluates local clustering or spatial autocorrelation International Journal of Preventive Medicine, Vol 4, No 10, October, 2013 1123 www.mui.ac.ir Goli, et al.: The mapping cancer in Fars province Figure 1: Map of counties of Fars province by computing the contribution of each location to RESULTS [28,29] the Moran’s I statistics for the whole study area. A total of 28,411 new cases were diagnosed Moran’s I is a weighted correlation coefficient with cancer in 2001‑2009 in Fars, 15,759 (55.5%) that takes values in the range (−1, 1). If value of of which were men. The average age of cases was Moran’s I is a significant positive value, it indicates 61.6 ± 0.5 year, and it breaks down to 63.8 ± 0.6 for positive spatial autocorrelation, which means, a men and 58.8 ± 0.8 for women.