Burden of Esophageal Cancer According to World Health Organization Regions: Review of Findings from the Global Burden of Disease Study 2015

authors:

avatar Azin Nahvijou ORCID 1 , avatar Mohamad Arab 2 , avatar Ahmad Faramarzi ORCID 3 , * , avatar Seyed Yaser Hashemi 4 , avatar Javad Javan-Noughabi 5

Cancer Research Center, Cancer Institute of Iran, Tehran University of Medical Sciences, Tehran, Iran
Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Department of Health Management and Economics, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Health Management and Economics Research Center, Iran University of Medical Sciences, Tehran, Iran

how to cite: Nahvijou A, Arab M, Faramarzi A, Hashemi S Y, Javan-Noughabi J. Burden of Esophageal Cancer According to World Health Organization Regions: Review of Findings from the Global Burden of Disease Study 2015. Health Scope. 2019;8(3):e64984. https://doi.org/10.5812/jhealthscope.64984.

Abstract

Background:

Esophageal carcinoma is regarded as a malignant disease with fatal consequences. In cancers, it was the sixth cause of death in the world, with an estimated 439025 deaths in 2015.

Objectives:

We conducted a research to evaluate the esophageal carcinoma burden based on the World Health Organization regions, during 2000 to 2015.

Methods:

Global Burden of Disease (GBD) was used to retrospectively collect the data from 2000 to 2015. The Institute for Health Metrics and Evaluation publishes the data. We utilized disability adjusted life years (DALY), incidence rate and prevalence rate to describe the esophageal cancer burden in the world.

Results:

In 2015, there were a total of 9854406 DALYs attributed to esophageal cancer where the majority were related the years of life lost (YLL) (9725791), and 128613 of the total were concerned with years lost due to disability (YLD). The highest of DALYs was in the Western Pacific region with 4773660 of the total. The Eastern Mediterranean region, with 516412 DALYs, shows the lowest number.

Conclusions:

The esophageal carcinoma is still a public health problem in high incidence countries. In all countries, the majority of the DALYs is related to YLL, indicating that prevention and early detection should be taken seriously. The burden of esophageal cancer is different in geographical regions. Therefore, a suitable and specific program in every region and country should be developed.

1. Background

Esophageal carcinoma is considered as a malignant disease with deadly consequences in developed and developing countries (1, 2). Between cancers, it is the sixth cause of death in the world, with an estimated 439025 deaths in 2015 (3, 4).

The burden of esophageal cancer widely varies across the world, with a disability adjusted life years (DALYs) of 516412 in Eastern Mediterranean and 4773660 in Western Pacific regions (4). In 2012, age-standardized incidence rate (ASR) of esophageal cancer was 0.8 per 100.000 people for men in Western Africa, 13.7 in Southern Africa and 17 in Eastern Asia (3). Although the incidence rate of the esophageal cancer is high, the survival rate is low in patients suffering from this disease. The survival rate of esophageal cancer has remained low over the last decades, especially in developing countries. Studies have shown that the 5-year survival rate is less than 20% in men. For instance, Harirchi et al. showed that it was less than 15% in Iran (5-7).

Studies concerned with the burden of cancers are used to measure the progress of the health sector, providing a comprehensive assessment of incidence, mortality, and disability for all the cancers. Furthermore, it determines the priorities for interventions and decisions (8).

According to literature, studies calculating the burden of esophageal cancer are classified into two groups. The first group is related to the epidemiology of esophageal cancer, including, number of deaths, prevalence, incidence, and mortality rate (9-11).

The other group is linked to studying the morbidity of esophageal cancer. These studies calculate the total time lost concerning premature death and disability. The DALY, years of life lost (YLL) and years lived with disability (YLD) is applied in these researches (8, 12, 13).

2. Objectives

In this research, we present a study to assess the burden of the esophageal cancer based on the World Health Organization regions, during 2000 to 2015. Moreover, we applied the DALY indicator to describe the esophageal cancer burden, using the Global Burden of Disease (GBD) methods. This study would be helpful for health policy makers in countries located in the esophageal cancer belt, such as the Islamic Republic of Iran, since the studies of cancer burden help to evaluate the budgetary impacts of health plans and provide a background for designing cost-effectiveness studies.

3. Methods

Global Burden of Disease (GBD) was used to retrospectively collect the data, from 2000 to 2015. The Institute for Health Metrics and Evaluation (IHME) publishes the GBD studies. In the GBD research, the primary data are number of deaths and disabilities. These data are collected and reported based on age groups and sex, for more than 350 disease and injuries. Moreover, the GBD provides a tool to quantify health loss, these instruments include death numbers, mortality rates, YLLs, YLDs, and DALYs. Various sources are used to calculate the morbidity and mortality indicator, including, the registration of the vital event, verbal autopsy, surveillance of the maternal and child death, and other sources. A detailed description of methods of the GBD study has been published in the references (14-16).

For the estimation of esophageal cancer burden we applied the DALY indicator. It was first designed by the World Health Organization (WHO) to compute and evaluate the burden of diseases (17, 18). This measure mixes the years of life lost and years lived with disability for a special cause. The DALY is obtained by summing YLLs and YLDs for each sex and age group in a given year. In general, a DALY is equivalent to losing one year of healthy life extracted from the combination of mortality and morbidity (19, 20).

The YLLs measure the lost years of life due to deaths, therefore for a given cause, age, and sex, this metric is equal to the death number multiplied by the standard life expectancy (17). The YLD measures the disability due to a specific cause in a particular time period. It is determined by multiplying the incidence number for a specific reason by the duration of disability and a weight factor (21).

To estimate the esophageal cancer burden in the world, we have linked the DALYs related to the cancer of esophagus based on the World Health Organization regions. We have carried out the following steps.

First, we divided countries according to the WHO regions. The burden of esophageal cancer was obtained by the GBD 2015, including incidence rate, prevalence rate, number of death and DALY. The WHO regions include the Western Pacific, Eastern Mediterranean, European, South East Asia, Pan American and African region. Second, to get a view of the burden of the disease, we selected 5 top countries with a high value of DALY in each region of the WHO. Third, we compared the burden of the esophageal cancer in WHO regions and 5 top countries with a high value of DALY. For a more detailed study, the burden of esophageal cancer was surveyed during 2000 to 2015.

In this study, we report the burden of esophageal cancer using age groups and sex. The age groups are under 14 years, 15 - 49 years, 50 - 69 years and > 70 years. Furthermore, we depicted the esophageal cancer burden based on YLL and YLD. We used the STATA package, version 13 for our analysis.

4. Results

4.1. Incidence, Prevalence and Death

In 2015, there were 439025 global deaths caused by esophageal cancer where the global incidence and global prevalence rate were 6.54 and 10.12 per 100.000 people, respectively. Table 1 displays the death number, rate of incidence and prevalence for esophageal carcinoma, relative to the world areas. The Western Pacific with a death number of 225672 (more than 50%) is ranked first, and the Eastern Mediterranean area with a death number of 1774 is at the end of the ranking. The incidence and prevalence rate for the Western Pacific is more than 2 times of the global average. More than half of the deaths caused by esophageal cancer happened in China, having a death number of 202042. It is worth mentioning that Japan has the highest incidence (22.29 per 100.000) and prevalence rate (54.62 per 100.000).

Table 1.

The Death Number, the Rate of Incidence and Prevalence in Top Five Countries in the WHO Regions, in 2015.

Region and Country Name (Number of Deaths)Incidence Rate per 100.000 PeoplePrevalence Rate per 100.000 People
Western Pacific (225672)13.8522.21
China (202042)Japan (22.29)Japan (54.62)
Japan (13717)China (15.66)China (23.42)
Vietnam 3791)Mongolia (12.14)New Zealand (17.80)
South Korea (2085)New Zealand (8.66)Mongolia (15)
Australia (1496)Ausralia (7.83)Ausralia (14.7)
Eastern Mediterranean (17741)2.583.28
Pakistan (10253)Afghanistan (1.69)Pakistan (6.41)
Iran (3261)United Arab Emirates (1.49)Iran (6.09)
Afghanistan (673)Morocco (1.22)Djibouti (5.66)
Egypt (649)Lebanon (1.19)Somalia (3.85)
Somalia (546)Yemen (0.97)United Arab Emirates (2.66)
European (52584)6.9412.22
United Kingdom (8376)Netherlands (18.02)Netherlands (34)
Russia (7927)United Kingdom (14.64)France (26.38)
Germany (5884)France (12.68)United Kingdom (24.20)
France (5526)Belgium (9.71)Hungary (20.6)
Italy (2379)Ireland (9.43)Belgium (19.3)
South East Asia (66628)3.404.48
India (49158)North Korea (12)North Korea (1595)
Indonesia (4981)Thailand (5.43)Thailand (8.30)
Bangladesh (3488)Sri Lanka (4.39)Sri Lanka (6.59)
Thailand (3330)India (3.67)India (4.78)
North Korea (3040)Bangladesh (2.05)Indonesia (2.65)
Pan American (40114)4.667.68
United States (17588)Uruguay (11.01)Cuba (16.33)
Brazil (10895)Cuba (8.99)Uruguay (15.49)
Argentina (2581)Barbados (8.54)Barbados (15.44)
Canada (2198)Canada (6.97)Puerto Rico (14.18)
Mexico (1355)Puerto Rico (6.87)United States (11.92)
African (33844)2.983.15
South Africa (5238)Malawi (10.42)South Africa (12.6)
Ethiopia (4090)South Africa (9.64)Seychelles (11.64)
Nigeria (2564)Lesotho (9.4)Botswan (10.62)
Uganda (2403)Swaziland (9.15)Malawi (10.32)
Democratic Republic of the Congo (2230)Botswana (8.97)Swaziland (10.06)
Global (439025)6.5410.12

4.2. DALY

In 2015, there were a total of 9854406 DALYs attributed to esophageal cancer, where the majority were related to the years of life lost (YLL) (9725791), and 128613 of the total were concerned with years lost due to disability (YLD). The worldwide DALY value is 7331669 and 2022737 for men and women, respectively. The greatest burden of DALYs has happened in the Western Pacific (4773660). The Eastern Mediterranean region with 516412 DALYs showed the lowest number. Table 2 indicates the number of DALYs due to esophageal cancer, according to the WHO areas.

Table 2.

The Number DALYs Reported for the Top Five Countries in each WHO Region, in 2015

Region and Country NameYLLYLDDALY
MaleFemaleMaleFemaleMaleFemaleTotal
Western Pacific region367766410273125167317010372933810443234773660
China3322076943618419701465933640479582784322325
Japan201045300617394144120844031502239942
Vietnam5911324508637367597512487584626
Australia19477575033619819814594825762
Malaysia7180364893507274369910973
Eastern Mediterranean26278824928422582080265046251365516412
Pakistan15035917307511381335151498174410325909
Iran4579827724535341463332806674399
Afghanistan734712905528373991298920388
Egypt1233956981135512452575318206
Somalia8351629858448409634314753
European region8632092170661333246278765422216941098236
Russia15406928015180553915587428554184428
United Kingdom10187438887158891710346339805143268
Germany950682255617224899679123046119837
France937521606718935179564616585112231
Ukraine43866383373110344597393748535
Southeast Asia region109363956892010685637611043245752971679621
India800183440550762248018078054453521253157
Indonesia75056521557705907582752746128573
Bangladesh7093513364683156716191352085140
Thailand5417018244704297548751854273417
North Korea4865223948476295491292424373373
Pan American region67853315879195553061688088161852849940
United States299982583174738131430472059631364352
Brazil20874448126240175721114648884260031
Argentina3660311722491231370941195449048
Canada33844736551516834359753341893
Mexico21029713729311621323725328576
African region61193425872747832297616717261025877743
South Africa84280361728194488510036620121720
Ethiopia62446387774813306292739107102035
Nigeria5776912705506127582761283271109
Uganda4304820223306161433542038463739
Malawi4340118586283133436851871962405
Global723866324871289300535608733166925227379854406

Table 3 shows the DALY number, according to the age group. In all the regions and countries, the highest burden is related to the age group of 50 - 69 years.

Table 3.

The Number DALYs Reported According to the Age Group for the Top Five Countries in each WHO Region, in 2015

Region and Country NameAge Groups
Under 1415 - 49 years50 - 69 years70+ years
Western Pacific region050861030141821308584
China046337527756551159027
Japan0913511946993140
Vietnam0184944675918750
Australia02440143939739
Malaysia0173956492787
Eastern Mediterranean013319518708850964
Pakistan09286610781021834
Iran0101032661513613
Afghanistan0527172621902
Egypt08681168683473
Somalia0255154701705
European region0117812663746285485
Russia01769612983433087
United Kingdom0116367606360461
Germany0102156788836519
France087666509927813
Ukraine06037343306914
Southeast Asia region0378926726381219207
India0287922549866156293
Indonesia016083235426457
Bangladesh0273122326110155
Thailand0148743931412395
North Korea0142404717720290
Pan American region0114993503653216483
United States036414230041102296
Brazil04750915512245757
Argentina052822550615767
Canada038762572013272
Mexico06395144907209
African region0176148361558120557
South Africa0192456575618472
Ethiopia0172072807714201
Nigeria013652282977664
Uganda014807311289848
Malawi021492277408924
Global0144459254942402211606

Figure 1 shows the trend of DALYs regarding esophageal cancer in the world, from 2000 to 2015, classified by the WHO areas. The findings indicated that the burden of esophageal cancer has had little change, from 2000 to 2015, of which the peak was more than 10 million DALYs in 2005. The majority of DALYs are distributed in the Western Pacific, in all the years.

DALYs number of esophageal cancer in WHO regions, 2000 to 2015
DALYs number of esophageal cancer in WHO regions, 2000 to 2015

Figure 2 shows the number of DALYs for top five countries, during 2000 to 2015. In all the years, China showed the highest value, but its trend has significantly declined. Other countries have an increasing trend during 2000 to 2015.

DALYs number due to esophageal cancer for top five countries, 2000 to 2015.
DALYs number due to esophageal cancer for top five countries, 2000 to 2015.

Figure 3 shows the DALY rate per 100.000 people in the top five countries. The same as the number of DALYs, in all the years, China has the highest DALY rate, but its trend has significantly diminished. India has the second rank in the DALY number, but it is at the bottom of the rank in the DALY rate.

DALY rate per 100.000 for top five countries, 2000 to 2015
DALY rate per 100.000 for top five countries, 2000 to 2015

5. Discussion

In this study, we have provided a comprehensive report on the burden of esophageal cancer, based on the WHO areas. The reports indicated that the trend of the esophageal cancer burden has increased by 2005. Then, it has diminished. In addition, the pattern for the esophageal cancer burden, based on geographical distribution, has been investigated.

About 439025 deaths and 9854406 DALYs of esophageal cancer happened in 2015. The global incidence and prevalence rates were 6.54 and 10.12 per 100.000, respectively. In 2015, according to the WHO regions, the Western Pacific area with more than 50% of the number of deaths (225672) and DALYs (4773660), compared to other regions, ranked first in the esophageal cancer burden. The Mediterranean region with a death number of 17741 and DALY of 516412 was indicated as the last rank.

Moreover, in 2015, the results showed that the incidence and prevalence rates of the esophageal cancer in the Western Pacific region were 13.85 and 22.21 per 100.000 people, respectively, almost twice the global average. In this area, Japan and China led to the highest incidence, prevalence and number of death. In Japan, incidence and prevalence rates are reported 22.29 and 54.62, respectively.

Mainly, China and Japan have caused the increased burden of esophageal cancer in the Pacific region. Esophageal cancer has always been a serious issue in these countries. In 2008, a study showed that esophageal cancer has led to 11746 and 211084 deaths in Japan and China, respectively (22).

The current study clearly demonstrated that the DALYs related to esophageal cancer in men (7331669) are higher than in women (2522737). However, there are two countries (Afghanistan and Pakistan) that their DALYs are higher among women. A study in Brazil estimated that the total DALYs of esophageal cancer was 3235 for men, and it was 918 for women (23). Another study in China reported that, per 100.000 people, the incidence rate of esophageal cancer was 10.39 in men, and it was 7.44 in women (24). In addition, a study showed that the incident cases of the esophageal cancer for men and women were 483000 and 352000, respectively (8). There is also a study indicating that the DALY rate of esophageal cancer for women is higher, in comparison with those in men (25).

In this study, the greatest cancer burden of the esophagus is related to the age group of 50 - 69 years, in all the WHO regions and countries. In some countries, however, the burden of esophageal cancer, in the age group of 15 to 49 years, is higher than the age group of < 70 years. For example, in the region of the Africa, the DALY number was 176148 and 120557 for the age groups of 15 - 49 and < 70 years, respectively. This finding suggests that the risk factors of esophageal cancer are different in the world. It is very important to consider that the burden of esophageal cancer varies depending on lifestyle, the factor of genetics and environmental effect (26, 27).

Our research, like the results of previous studies, displays that the YLLs are a major part of DALYs calculation for esophageal carcinoma burden. It is presented that esophageal carcinoma has a high mortality. In China, the research found that more than 90% of the DALY for esophageal carcinoma were due to premature death (28). Jayatilleke et al. have reported that YLL contributed to the majority of the DALY rate (90%) for esophageal carcinoma, in all ages (29). Another study, in 2010, estimating the burden of diseases between Mexican people, reported that YLL and YLD were 6032 and 690, for esophageal cancer, respectively (12).

For more careful study on the burden of esophageal cancer, we assessed the DALY, in 2000 to 2015. Globally, DALYs were 1023116 in 2000, gained the peak of 10665358 in 2005. Then, decreased by 2015. Regionally, the Western Pacific area always has the highest DALY, in all the years, where DALYs were 5968131 and 4773660, in 2000 and 2015, respectively. The lowest DALYs happened in the Mediterranean area during these years. Internationally, in 2015, the top 5 countries which had the highest esophageal cancer DALYs were China, India, United States, Pakistan and Brazil. The following points should be noted when one wants to review the esophageal cancer burden in the 5 top countries and WHO areas. Firstly, although the Western Pacific area always had the highest DALYs related to esophageal cancer, the trend of DALY has been decreasing in this area. In addition, China is located in the Western Pacific area, and it has more than half of the global DALYs.

Secondly, China had the highest DALYs during 2000 to 2015 whereas the trend of esophageal cancer DALYs has been decreasing. On the other hand, it has been increasing in other countries.

These findings further support the idea of which countries of Asia are also located on the esophageal cancer belt. This area expands from Northern China through Southern Russia, Northern Afghanistan and North-Eastern Iran to Eastern Turkey (30). All the countries located at the esophageal cancer belt, except Turkey, have a high burden of the esophageal cancer in our study.

Interpretation of the results based on the geographical area shows a series of homogeneous and heterogeneous patterns associated with the burden of the esophageal cancer. First, in all the areas and countries, age and sex are important factors for the esophageal burden. Second, in all the geographical areas, the burden of esophageal cancer is more related to YLL. Third, the African region and its countries have a special pattern. In the countries of this region, the burden of the esophagus in the age group of 15 - 49 years is more than the age group of > 70 years.

Despite the fact that the GBD study is effective in estimating the global burden of diseases, it has some critical limitations. It does not distinguish between the esophageal cancer burden by its subtype. This could be a topic for upcoming studies since each has its own burden of disease. Moreover, adenocarcinoma of the esophagus is more common in developed countries, particularly the United States (31). In developing countries, the squamous cell carcinoma of esophageal is more common (32).

The assessment of GBD study is contingent on the accessibility of data sources due to the delay time for data reporting. It may result in a miscalculated cancer burden for countries where there does not exist a complete system to register and report the cancers. For instance, studies have revealed that in some regions of Iran, the rate of incidence and prevalence for esophageal cancer are much higher than estimations conducted in GBD study (33, 34).

5.1. Conclusions

Esophageal cancer is still a public health issue in the world. In all counties, the majority of DALYs were related to YLL, indicating that prevention and early detection should be seriously considered. Regionally, the burden of disease is different according to the WHO regions. Therefore, a specific and suitable program should be used in every region and country. In addition, the burden of esophageal cancer is more about the elderly people, suggesting that health policy makers pay more attention to programs related to health of the elderly people, especially in developing countries.

Acknowledgements

References

  • 1.

    Li L, Zhang C, Li X, Lu S, Zhou Y. The candidate tumor suppressor gene ECRG4 inhibits cancer cells migration and invasion in esophageal carcinoma. J Exp Clin Cancer Res. 2011;30:19. [PubMed ID: 21324197]. [PubMed Central ID: PMC3047428]. https://doi.org/10.1186/1756-9966-30-19.

  • 2.

    Li T, Suo Q, He D, Du W, Yang M, Fan X, et al. Esophageal cancer risk is associated with polymorphisms of DNA repair genes MSH2 and WRN in Chinese population. J Thorac Oncol. 2012;7(2):448-52. [PubMed ID: 22173703]. https://doi.org/10.1097/JTO.0b013e31823c487a.

  • 3.

    Ferlay J, Soerjomataram I, Dikshit R, Eser S, Mathers C, Rebelo M, et al. Cancer incidence and mortality worldwide: Sources, methods and major patterns in GLOBOCAN 2012. Int J Cancer. 2015;136(5):E359-86. [PubMed ID: 25220842]. https://doi.org/10.1002/ijc.29210.

  • 4.

    Global burden of disease study 2015. 2015. Available from: http://ghdx.healthdata.org/gbd-results-tool.

  • 5.

    Harirchi I, Kolahdoozan S, Hajizadeh S, Safari F, Sedighi Z, Nahvijou A, et al. Esophageal cancer in Iran; a population-based study regarding adequacy of cancer surgery and overall survival. Eur J Surg Oncol. 2014;40(3):352-7. [PubMed ID: 24238763]. https://doi.org/10.1016/j.ejso.2013.10.011.

  • 6.

    Samson P, Puri V, Broderick S, Patterson GA, Meyers B, Crabtree T. Adhering to quality measures in esophagectomy is associated with improved survival in all stages of esophageal cancer. Ann Thorac Surg. 2017;103(4):1101-8. [PubMed ID: 28109569]. [PubMed Central ID: PMC5444909]. https://doi.org/10.1016/j.athoracsur.2016.09.032.

  • 7.

    Wang C, Fu X, Cai X, Wu X, Hu X, Fan M, et al. High-dose nimotuzumab improves the survival rate of esophageal cancer patients who underwent radiotherapy. Onco Targets Ther. 2016;9:117-22. [PubMed ID: 26766917]. [PubMed Central ID: PMC4699509]. https://doi.org/10.2147/OTT.S89592.

  • 8.

    Fitzmaurice C, Allen C, Barber RM, Barregard L, Bhutta ZA; Global Burden of Disease Cancer Collaboration, et al. Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-adjusted life-years for 32 cancer groups, 1990 to 2015: A systematic analysis for the global burden of disease study. JAMA Oncol. 2017;3(4):524-48. [PubMed ID: 27918777]. [PubMed Central ID: PMC6103527]. https://doi.org/10.1001/jamaoncol.2016.5688.

  • 9.

    Ghasemi-Kebria F, Roshandel G, Semnani S, Shakeri R, Khoshnia M, Naeimi-Tabiei M, et al. Marked increase in the incidence rate of esophageal adenocarcinoma in a high-risk area for esophageal cancer. Arch Iran Med. 2013;16(6):320-3.

  • 10.

    Bray F, Jemal A, Grey N, Ferlay J, Forman D. Global cancer transitions according to the Human Development Index (2008-2030): A population-based study. Lancet Oncol. 2012;13(8):790-801. [PubMed ID: 22658655]. https://doi.org/10.1016/S1470-2045(12)70211-5.

  • 11.

    Jemal A, Bray F, Center MM, Ferlay J, Ward E, Forman D. Global cancer statistics. CA Cancer J Clin. 2011;61(2):69-90. [PubMed ID: 21296855]. https://doi.org/10.3322/caac.20107.

  • 12.

    Gonzalez-Leon M, Fernandez-Garate JE, Rascon-Pacheco RA, Valladares-Aranda MA, Davila-Torres J, Borja-Aburto VH. The burden of disease of cancer in the Mexican Social Security Institute. Salud Publica Mex. 2016;58(2):132-41. [PubMed ID: 27557371].

  • 13.

    Fitzmaurice C, Dicker D, Pain A, Hamavid H, Moradi-Lakeh M; Global Burden of Disease Cancer Collaboration, et al. The global burden of cancer 2013. JAMA Oncol. 2015;1(4):505-27. [PubMed ID: 26181261]. [PubMed Central ID: PMC4500822]. https://doi.org/10.1001/jamaoncol.2015.0735.

  • 14.

    Murray CJ, Vos T, Lozano R, Naghavi M, Flaxman AD, Michaud C, et al. Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990-2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012;380(9859):2197-223. [PubMed ID: 23245608]. https://doi.org/10.1016/S0140-6736(12)61689-4.

  • 15.

    Wang H, Dwyer-Lindgren L, Lofgren KT, Rajaratnam JK, Marcus JR, Levin-Rector A, et al. Age-specific and sex-specific mortality in 187 countries, 1970-2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012;380(9859):2071-94. [PubMed ID: 23245603]. https://doi.org/10.1016/S0140-6736(12)61719-X.

  • 16.

    Lopez AD, Mathers CD. Measuring the global burden of disease and epidemiological transitions: 2002-2030. Ann Trop Med Parasitol. 2006;100(5-6):481-99. [PubMed ID: 16899150]. https://doi.org/10.1179/136485906X97417.

  • 17.

    Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJL. Global burden of disease and risk factors. Washington (DC); 2006.

  • 18.

    World Health Organization. WHO methods and data sources for global burden of disease estimates 2000-2015. Geneva: WHO, Department of Information EaRW; 2017.

  • 19.

    Murray CJ, Lopez AD, Jamison DT. The global burden of disease in 1990: Summary results, sensitivity analysis and future directions. Bull World Health Organ. 1994;72(3):495-509. [PubMed ID: 8062404]. [PubMed Central ID: PMC2486716].

  • 20.

    Sassi F. Calculating QALYs and DALYs: Methods and applications to fatal and non-fatal conditions. Handbook of disease burdens and quality of life measures. Springer; 2010. p. 313-28. https://doi.org/10.1007/978-0-387-78665-0_17.

  • 21.

    World Health Organization. WHO methods and data sources for global burden of disease estimates 2000-2011. Geneva: WHO, Department of Health Statistics and Information Systems; 2013.

  • 22.

    Lin Y, Totsuka Y, He Y, Kikuchi S, Qiao Y, Ueda J, et al. Epidemiology of esophageal cancer in Japan and China. J Epidemiol. 2013;23(4):233-42. [PubMed ID: 23629646]. [PubMed Central ID: PMC3709543]. https://doi.org/10.2188/jea.je20120162.

  • 23.

    Traebert J, Schneider IJ, Colussi CF, de Lacerda JT. Burden of disease due to cancer in a Southern Brazilian state. Cancer Epidemiol. 2013;37(6):788-92. [PubMed ID: 24035552]. https://doi.org/10.1016/j.canep.2013.08.007.

  • 24.

    Chen W, He Y, Zheng R, Zhang S, Zeng H, Zou X, et al. Esophageal cancer incidence and mortality in China, 2009. J Thorac Dis. 2013;5(1):19-26. [PubMed ID: 23372946]. [PubMed Central ID: PMC3547988]. https://doi.org/10.3978/j.issn.2072-1439.2013.01.04.

  • 25.

    Di Pardo BJ, Bronson NW, Diggs BS, Thomas CR Jr, Hunter JG, Dolan JP. The global burden of esophageal cancer: A disability-adjusted life-year approach. World J Surg. 2016;40(2):395-401. [PubMed ID: 26630937]. https://doi.org/10.1007/s00268-015-3356-2.

  • 26.

    Zhang Y. Epidemiology of esophageal cancer. World J Gastroenterol. 2013;19(34):5598-606. [PubMed ID: 24039351]. [PubMed Central ID: PMC3769895]. https://doi.org/10.3748/wjg.v19.i34.5598.

  • 27.

    Eslick GD. Epidemiology of esophageal cancer. Gastroenterol Clin North Am. 2009;38(1):17-25. vii. [PubMed ID: 19327565]. https://doi.org/10.1016/j.gtc.2009.01.008.

  • 28.

    Sun X, Zhao D, Liu Y, Liu Y, Yuan Z, Wang J, et al. The long-term spatial-temporal trends and burden of esophageal cancer in one high-risk area: A population-registered study in Feicheng, China. PLoS One. 2017;12(3). e0173211. [PubMed ID: 28267769]. [PubMed Central ID: PMC5340364]. https://doi.org/10.1371/journal.pone.0173211.

  • 29.

    Jayatilleke N, Pashayan N, Powles JW. Burden of disease due to cancer in England and Wales. J Public Health (Oxf). 2012;34(2):287-95. [PubMed ID: 22138490]. https://doi.org/10.1093/pubmed/fdr093.

  • 30.

    Conteduca V, Sansonno D, Ingravallo G, Marangi S, Russi S, Lauletta G, et al. Barrett's esophagus and esophageal cancer: An overview. Int J Oncol. 2012;41(2):414-24. [PubMed ID: 22615011]. https://doi.org/10.3892/ijo.2012.1481.

  • 31.

    Trivers KF, Sabatino SA, Stewart SL. Trends in esophageal cancer incidence by histology, United States, 1998-2003. Int J Cancer. 2008;123(6):1422-8. [PubMed ID: 18546259]. https://doi.org/10.1002/ijc.23691.

  • 32.

    Law S, Wong J. Changing disease burden and management issues for esophageal cancer in the Asia-Pacific region. J Gastroenterol Hepatol. 2002;17(4):374-81. [PubMed ID: 11982715].

  • 33.

    Kolahdoozan S, Sadjadi A, Radmard AR, Khademi H. Five common cancers in Iran. Arch Iran Med. 2010;13(2):143-6. [PubMed ID: 20187669].

  • 34.

    Sadjadi A, Marjani H, Semnani S, Nasseri-Moghaddam S. Esophageal cancer in iran: A review. Middle East J Canc. 2010;1(1):5-14.