Ahmedin Jemal

Bio: Ahmedin Jemal is an academic researcher from American Cancer Society. The author has contributed to research in topics: Cancer & Population. The author has an hindex of 132, co-authored 500 publications receiving 380474 citations. Previous affiliations of Ahmedin Jemal include Centers for Disease Control and Prevention & Emory University.

Preventing Lung Cancer Mortality by Computed Tomography Screening: The Effect of Risk-Based Versus U.S. Preventive Services Task Force Eligibility Criteria, 2005-2015.

Abstract: Background: The U.S. Preventive Services Task Force (USPSTF) recommends annual low-dose computed tomography (CT) lung cancer screening for persons aged 55 to 80 years who currently smoke or quit within the past 15 years and have at least a 30pack-year history of cigarette smoking (1). The number of U.S. persons meeting USPSTF criteria for CT screening sharply decreased between 2010 and 2015 (2). However, these criteria may exclude smokers at high risk for lung cancer who would have been selected for CT screening by individual risk calculators that more specifically account for demographic, clinical, and smoking characteristics (3). Objective: To compare USPSTF eligibility criteria with individualized, risk-based eligibility and estimate the effect of eligibility on lung cancer deaths preventable by screening since 2005. Methods and Findings: We used data from 5460, 5155, and 6971 ever-smokers aged 50 to 80 years without self-reported lung cancer from the nationally representative National Health Interview Survey from 2005, 2010, and 2015, respectively (2). Individual 5-year risks for lung cancer incidence and death were estimated using the previously validated Lung Cancer Risk Assessment Tool and Lung Cancer Death Risk Assessment Tool (3). We estimated the number of U.S. smokers aged 50 to 80 years who were eligible by USPSTF criteria or by an individual 5-year risk for lung cancer incidence of at least 1.5%, 2.0%, or 2.5% using the Lung Cancer Risk Assessment Tool (3). Using the difference in Lung Cancer Death Risk Assessment Toolestimated individual risks for lung cancer death with and without screening (3), we estimated the number of deaths from lung cancer preventable by screening according to each eligibility criteria among the U.S. population of ever-smokers aged 50 to 80 years (3). Finally, we estimated the number of U.S. smokers in subgroups eligible and ineligible for screening according to USPSTF criteria. Statistical analysis was conducted using the survey package (4) for R, version 3.4.1 (R Foundation for Statistical Computing). The number of screening-eligible ever-smokers by any eligibility criteria increased between 2005 and 2010 but decreased between 2010 and 2015. In particular, the number of persons eligible for screening according to USPSTF criteria increased from 8.7 million (24.6% of U.S. ever-smokers aged 50 to 80 years) in 2005 to 9.5 million (22.8% of U.S. ever-smokers aged 50 to 80 years) in 2010 but decreased substantially to 8.0 million (18.4% of U.S. ever-smokers aged 50 to 80 years) in 2015, a decline of 1.5 million ever-smokers (Figure 1, A). However, the decreases in screening eligibility between 2010 and 2015 were more modest for risk-based criteria. For example, the number of U.S. smokers with a 5-year lung cancer risk of at least 2.0% decreased by only 0.8 million between 2010 and 2015 (from 9.4 to 8.6 million), one half the decrease based on USPSTF criteria (P= 0.048). Similarly, the decreases between 2010 and 2015 in the number of persons eligible for screening based on having a 5-year lung cancer risk of at least 1.5% and 2.5% were only 0.7 and 0.8 million, respectively. Figure 1. Estimated number of ever-smokers eligible for screening and percentage of all U.S. lung cancer deaths preventable by screening averted by USPSTF and risk-based criteria for screening eligibility, 20052015*. A. U.S. ever-smokers aged 5080 y in 2005, 2010, and 2015 who would have been eligible for screening with low-dose CT by USPSTF criteria and by reaching 5-y lung cancer risk thresholds of 1.5%, 2.0%, and 2.5%. B. Percentage of lung cancer deaths preventable by screening among U.S. ever-smokers aged 5080 y averted by USPSTF criteria or by 5-y lung cancer risk thresholds of 1.5%, 2.0%, and 2.5% in 2005, 2010, and 2015. * Error bars represent 95% CIs. For each year of the National Health Interview Survey (available at www.cdc.gov/nchs/nhis), we used 5 multiple imputation data sets to account for missing information on certain characteristics (3). The following numbers of respondents were missing data for these items for 2005, 2010, and 2015, respectively: race, 50, 92, and 128; education, 29, 17, and 27; body mass index, 151, 127, and 202; quit years, 33, 12, and 25; cigarettes smoked per day, 252, 366, and 512; years smoked, 28, 9, and 20; emphysema, 5, 9, and 13); and family history of lung cancer, 146, 102, and 846. Risks for lung cancer incidence and death were estimated using the Lung Cancer Risk Assessment Tool and Lung Cancer Death Risk Assessment Tool, respectively (available at https://dceg.cancer.gov/tools/risk-assessment/lcrisks). CT = computed tomography; USPSTF = U.S. Preventive Services Task Force. The number of ever-smokers with a 5-y lung cancer risk2.5% decreased between 2010 and 2015 from 7.35 million to 6.54 million, a decline of 0.81 million. U.S. lung cancer deaths preventable by screening between 2010 and 2015 decreased from 61.64% to 57.96%, a decrease of 3.68 percentage points. The percentage of U.S. lung cancer deaths preventable by screening that would be averted using each eligibility criteria likewise decreased between 2005 and 2015 (Figure 1, B). Between 2010 and 2015, preventable lung cancer deaths averted by using the USPSTF criteria decreased by 6.4 percentage points (8122 fewer deaths averted in 2015 than in 2010). However, those averted by using 5-year lung cancer risk thresholds of 1.5%, 2.0%, and 2.5% decreased by a more modest 2.6, 3.2, and 3.7 percentage points, respectively (approximately 6000 fewer deaths averted in 2015 than in 2010 for each). Using a 5-year lung cancer risk of at least 2.5% instead of USPSTF criteria in 2005 would have prevented 2617 more lung cancer deaths (an increase of 3.5 percentage points) over 5 years (P< 0.001), but in 2015 the difference in prevented deaths increased to 5115 (an increase of 6.4 percentage points) (P< 0.001). Between 2010 and 2015, the 1.5-million decrease in the number of U.S. ever-smokers eligible for screening by USPSTF criteria was offset by an increase of 1.3 million in the number of U.S. ever-smokers with a 20 to 29pack-year history who otherwise met USPSTF criteria (Figure 2). These smokers may have had sufficiently high individual risk for lung cancer (5) to be eligible for screening by risk-based criteria. The decrease in the number of ever-smokers eligible for screening by USPSTF criteria may continue, because smoking prevalence and intensity have decreased substantially among younger persons in the 2015 U.S. population (a 47% prevalence with a mean of 16.9 cigarettes per day among persons aged 80 years compared with a 34% prevalence with a mean of 11.7 cigarettes per day among persons aged 40 years [P for trend < 0.001]). Figure 2. Number of U.S. ever-smokers eligible and ineligible for screening by USPSTF criteria, 20052015*. Median (interquartile range) 5-y individual risks for lung cancer incidence and death in the absence of computed tomography screening for smoking subgroups in 2015 are as follows: Current smokers with a30pack-year history aged 5580 y: incidence, 3.6% (2.2%6.4%); death, 2.2% (1.3%4.1%). Former smokers with a30pack-year history aged 5580 y: incidence, 2.0% (1.2%3.4%); death, 1.2% (0.7%2.3%). Current smokers or those who quit15 y ago with a30pack-year history aged 5055 y: incidence, 1.0% (0.7%1.4%); death, 0.4% (0.3%0.7%). Former smokers who quit 1520 y ago with a30pack-year history aged 5580 y: incidence, 1.4% (1.0%2.6%); death, 1.0% (0.6%1.9%). Former smokers who quit15 y ago with a 2029pack-year history aged 5580 y: incidence, 1.0% (0.4%1.5%); death, 0.5% (0.2%0.9%). Current smokers with a 2029pack-year history aged 5580 y: incidence, 1.8% (1.1%3.0%); death, 1.0% (0.6%1.7%). Median risks within subgroups in 2005 and 2010 are similar to those in 2015 (all within 0.2%). USPSTF= U.S. Preventive Services Task Force. * See the first footnote for Figure 1. Discussion: Although the number of U.S. ever-smokers eligible for lung cancer screening according to USPSTF criteria decreased by 1.5 million between 2010 and 2015, the number eligible for screening based on reaching risk threshold criteria decreased by only one half as much. Because of U.S. population changes related to smoking between 2010 and 2015, adhering to the USPSTF criteria led to fewer ever-smokers being eligible for CT screening and fewer lung cancer deaths being averted by screening. Individual risk-based criteria would screen high-risk smokers currently ineligible for screening using USPSTF criteria, resulting in more modest decreases in the numbers screened and deaths averted. To better capture high-risk smokers and prevent premature deaths from lung cancer, eligibility for lung cancer screening should be based on reaching a cost-effective risk threshold that balances CT screening benefits and harms by using a lung cancer risk tool validated in the U.S. population. The gap in screening effectiveness between risk-based and USPSTF screening criteria may continue to increase in the future.

Reducing Social Inequalities in Cancer: Setting Priorities for Research

Abstract: Social inequalities in cancer are a global problem, as has been well documented in the World Health Organization (WHO)/International Agency for Research on Cancer (IARC) publication Social Inequalities and Cancer. Inequalities in income, wealth, education, and power disproportionally impact the most disadvantaged individuals, communities, and countries to produce a social gradient in the incidence, survival, and mortality of many cancers both within and between countries. From April 16 to 18, 2018, the IARC convened a workshop to examine the current evidence and identify research priorities for reducing social inequalities in cancer. International and WHO/IARC experts drawn from many different disciplines presented a series of articles to be published in an IARC scientific publication; extensive discussion in subgroups and plenary sessions resulted in participants identifying 3 research priorities.

Knowledge about cervical cancer and barriers toward cervical cancer screening among HIV-positive women attending public health centers in Addis Ababa city, Ethiopia.

Abstract: Screening rate for cervical cancer among HIV-infected women and among women overall is low in Ethiopia despite the high burden of the disease and HIV infection, which increases cervical cancer risk. In this paper, we assessed knowledge about cervical cancer symptoms, prevention, early detection, and treatment and barriers to screening among HIV-positive women attending community health centers for HIV-infection management in Addis Ababa. A cross-sectional survey of 581 HIV-positive women aged 21-64 years old attending 14 randomly selected community health centers without cervical cancer screening service in Addis Ababa. We used univariate analysis to calculate summary statistics for each variable considered in the analysis, binary logistic regression analysis to measure the degree of association between dependent and independent variables, and multiple regressions for covariate adjusted associations. Statistical significance for all tests was set at P < 0.05. We used thematic analysis to describe the qualitative data. Of the 581 women enrolled in the study with mean age 34.9 ± 7.7 years, 57.8% of participants had heard of cervical cancer and 23.4% were knowledgeable about the symptoms, prevention, early detection, and treatment of the disease. In multivariate analysis, higher educational attainment and employment were significantly associated with good knowledge about cervical cancer. In addition, only 10.8% of the participants ever had screening and 17% ever received recommendation for it. However, 86.2% of them were willing to be screened if free of cost. Knowledge about cervical cancer is poor and cervical cancer screening rate and provider recommendation are low among HIV-positive women attending community health centers for management and follow-up of their disease in Addis Ababa. These findings underscore the need to scale up health education about cervical cancer prevention and early detection among HIV-positive women as well as among primary healthcare providers in the city.

The prevalence of estrogen receptor-negative breast cancer in Ethiopia

Abstract: In contrast with breast cancers (BCs) in other parts of the world, most previous studies reported that the majority of BCs in sub-Saharan Africa are estrogen-receptor (ER) negative. However, a recent study using the US SEER database showed that the proportion of ER-negative BC is comparable between US-born blacks and West-African born blacks but substantially lower in East African-born blacks, with over 74% of patients Ethiopians or Eritreans. In this paper, we provide the first report on the proportion of ER-negative BC in Ethiopia, and the relation to progesterone-receptor (PgR) status. We analysed 352 female patients with ER results available out of 1208 consecutive female BC patients treated at Addis Ababa-University Hospital, Ethiopia, from June 2005 through December 2010. The influences of age, stage, and histology on the probability of ER-negative tumours were assessed by a log-linear regression model. Of the 352 patients, only 35% were ER-negative. The proportion of ER-negative tumours decreased with advancing age at diagnosis and was not affected by histology or stage. For age, the proportion decreased by 6% for each additional 5 years (stage-adjusted prevalence ratio PR = 0.94, 95% CI: 0.89–1.00). About 31% were ER- and PgR-negative, and 69% were ER- and/or PgR-positive. Contrary to most previous reports in other parts of sub-Saharan Africa, the majority of patients in Ethiopia are ER-positive rather than ER-negative. These findings are in line with low proportions of ER-negative BCs from East African immigrants within the SEER database, and they have clinical implications for management of BC patients in Ethiopia and other parts of sub-Saharan Africa where ER-status is not ascertained as part of routine management of the disease. Since the majority of patients showed ER-positive BC, Tamoxifen-therapy should be given to all patients even with unknown ER status.

Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries

Abstract: This article provides a status report on the global burden of cancer worldwide using the GLOBOCAN 2018 estimates of cancer incidence and mortality produced by the International Agency for Research on Cancer, with a focus on geographic variability across 20 world regions There will be an estimated 181 million new cancer cases (170 million excluding nonmelanoma skin cancer) and 96 million cancer deaths (95 million excluding nonmelanoma skin cancer) in 2018 In both sexes combined, lung cancer is the most commonly diagnosed cancer (116% of the total cases) and the leading cause of cancer death (184% of the total cancer deaths), closely followed by female breast cancer (116%), prostate cancer (71%), and colorectal cancer (61%) for incidence and colorectal cancer (92%), stomach cancer (82%), and liver cancer (82%) for mortality Lung cancer is the most frequent cancer and the leading cause of cancer death among males, followed by prostate and colorectal cancer (for incidence) and liver and stomach cancer (for mortality) Among females, breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death, followed by colorectal and lung cancer (for incidence), and vice versa (for mortality); cervical cancer ranks fourth for both incidence and mortality The most frequently diagnosed cancer and the leading cause of cancer death, however, substantially vary across countries and within each country depending on the degree of economic development and associated social and life style factors It is noteworthy that high-quality cancer registry data, the basis for planning and implementing evidence-based cancer control programs, are not available in most low- and middle-income countries The Global Initiative for Cancer Registry Development is an international partnership that supports better estimation, as well as the collection and use of local data, to prioritize and evaluate national cancer control efforts CA: A Cancer Journal for Clinicians 2018;0:1-31 © 2018 American Cancer Society

Global cancer statistics

Abstract: The global burden of cancer continues to increase largely because of the aging and growth of the world population alongside an increasing adoption of cancer-causing behaviors, particularly smoking, in economically developing countries. Based on the GLOBOCAN 2008 estimates, about 12.7 million cancer cases and 7.6 million cancer deaths are estimated to have occurred in 2008; of these, 56% of the cases and 64% of the deaths occurred in the economically developing world. Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females, accounting for 23% of the total cancer cases and 14% of the cancer deaths. Lung cancer is the leading cancer site in males, comprising 17% of the total new cancer cases and 23% of the total cancer deaths. Breast cancer is now also the leading cause of cancer death among females in economically developing countries, a shift from the previous decade during which the most common cause of cancer death was cervical cancer. Further, the mortality burden for lung cancer among females in developing countries is as high as the burden for cervical cancer, with each accounting for 11% of the total female cancer deaths. Although overall cancer incidence rates in the developing world are half those seen in the developed world in both sexes, the overall cancer mortality rates are generally similar. Cancer survival tends to be poorer in developing countries, most likely because of a combination of a late stage at diagnosis and limited access to timely and standard treatment. A substantial proportion of the worldwide burden of cancer could be prevented through the application of existing cancer control knowledge and by implementing programs for tobacco control, vaccination (for liver and cervical cancers), and early detection and treatment, as well as public health campaigns promoting physical activity and a healthier dietary intake. Clinicians, public health professionals, and policy makers can play an active role in accelerating the application of such interventions globally.

Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries.

Abstract: This article provides an update on the global cancer burden using the GLOBOCAN 2020 estimates of cancer incidence and mortality produced by the International Agency for Research on Cancer. Worldwide, an estimated 19.3 million new cancer cases (18.1 million excluding nonmelanoma skin cancer) and almost 10.0 million cancer deaths (9.9 million excluding nonmelanoma skin cancer) occurred in 2020. Female breast cancer has surpassed lung cancer as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%), followed by lung (11.4%), colorectal (10.0 %), prostate (7.3%), and stomach (5.6%) cancers. Lung cancer remained the leading cause of cancer death, with an estimated 1.8 million deaths (18%), followed by colorectal (9.4%), liver (8.3%), stomach (7.7%), and female breast (6.9%) cancers. Overall incidence was from 2-fold to 3-fold higher in transitioned versus transitioning countries for both sexes, whereas mortality varied <2-fold for men and little for women. Death rates for female breast and cervical cancers, however, were considerably higher in transitioning versus transitioned countries (15.0 vs 12.8 per 100,000 and 12.4 vs 5.2 per 100,000, respectively). The global cancer burden is expected to be 28.4 million cases in 2040, a 47% rise from 2020, with a larger increase in transitioning (64% to 95%) versus transitioned (32% to 56%) countries due to demographic changes, although this may be further exacerbated by increasing risk factors associated with globalization and a growing economy. Efforts to build a sustainable infrastructure for the dissemination of cancer prevention measures and provision of cancer care in transitioning countries is critical for global cancer control.

Global cancer statistics, 2012

Abstract: Cancer constitutes an enormous burden on society in more and less economically developed countries alike. The occurrence of cancer is increasing because of the growth and aging of the population, as well as an increasing prevalence of established risk factors such as smoking, overweight, physical inactivity, and changing reproductive patterns associated with urbanization and economic development. Based on GLOBOCAN estimates, about 14.1 million new cancer cases and 8.2 million deaths occurred in 2012 worldwide. Over the years, the burden has shifted to less developed countries, which currently account for about 57% of cases and 65% of cancer deaths worldwide. Lung cancer is the leading cause of cancer death among males in both more and less developed countries, and has surpassed breast cancer as the leading cause of cancer death among females in more developed countries; breast cancer remains the leading cause of cancer death among females in less developed countries. Other leading causes of cancer death in more developed countries include colorectal cancer among males and females and prostate cancer among males. In less developed countries, liver and stomach cancer among males and cervical cancer among females are also leading causes of cancer death. Although incidence rates for all cancers combined are nearly twice as high in more developed than in less developed countries in both males and females, mortality rates are only 8% to 15% higher in more developed countries. This disparity reflects regional differences in the mix of cancers, which is affected by risk factors and detection practices, and/or the availability of treatment. Risk factors associated with the leading causes of cancer death include tobacco use (lung, colorectal, stomach, and liver cancer), overweight/obesity and physical inactivity (breast and colorectal cancer), and infection (liver, stomach, and cervical cancer). A substantial portion of cancer cases and deaths could be prevented by broadly applying effective prevention measures, such as tobacco control, vaccination, and the use of early detection tests.

Estimates of worldwide burden of cancer in 2008: GLOBOCAN 2008.

Abstract: Estimates of the worldwide incidence and mortality from 27 cancers in 2008 have been prepared for 182 countries as part of the GLOBOCAN series published by the International Agency for Research on Cancer. In this article, we present the results for 20 world regions, summarizing the global patterns for the eight most common cancers. Overall, an estimated 12.7 million new cancer cases and 7.6 million cancer deaths occur in 2008, with 56% of new cancer cases and 63% of the cancer deaths occurring in the less developed regions of the world. The most commonly diagnosed cancers worldwide are lung (1.61 million, 12.7% of the total), breast (1.38 million, 10.9%) and colorectal cancers (1.23 million, 9.7%). The most common causes of cancer death are lung cancer (1.38 million, 18.2% of the total), stomach cancer (738,000 deaths, 9.7%) and liver cancer (696,000 deaths, 9.2%). Cancer is neither rare anywhere in the world, nor mainly confined to high-resource countries. Striking differences in the patterns of cancer from region to region are observed.