Cancer in sub-Saharan Africa in 2020: a review of current estimates of the national burden, data gaps, and future needs.

BACKGROUND: With the cancer burden rising in sub-Saharan Africa, countries in the region need surveillance systems to measure the magnitude of the problem and monitor progress in cancer control planning. Based on the national estimates built from data provided by cancer registries in sub-Saharan Africa, we summarise key patterns of the regional burden and argue for investments in locally produced data. METHODS: To present national estimates of the cancer incidence and mortality burden in sub-Saharan Africa countries, new cancer cases and deaths were extracted from International Agency for Research on Cancers' GLOBOCAN database for the year 2020. Given weak vital statistics systems, almost all of the information on the cancer burden in sub-Saharan Africa was derived from population-based cancer registries. Of the 48 countries included in GLOBOCAN (national populations must be larger than 150 000 inhabitants in 2020), relatively recent cancer registry data (up to 2019) were directly used to produce national incidence estimates in 25 countries, while the absence of such data for 16 meant that estimates were based on data from neighbouring countries. Tables and figures present the estimated numbers of new cases and deaths, as well as age-standardised (incidence or mortality) rates per 100 000 person-years and the cumulative risk of developing or dying from cancer before the age of 75 years. FINDINGS: 801 392 new cancer cases and 520 158 cancer deaths were estimated to have occurred in sub-Saharan Africa in 2020. Cancers of the breast (129 400 female cases) and cervix (110 300 cases) were responsible for three in ten of the cancers diagnosed in both sexes. Breast and cervical cancer were the most common cancers, ranking first in 28 and 19 countries, respectively. In men, prostate cancer led in terms of incidence (77 300 cases), followed by liver cancer (24 700 cases) and colorectal cancer (23 400 cases). Prostate cancer was the leading incident cancer in men in 40 sub-Saharan Africa countries. The risk of a woman in sub-Saharan Africa developing cancer by the age of 75 years was 14·1%, with breast cancer (4·1%) and cervical cancer (3·5%) responsible for half of this risk. For men, the corresponding cumulative incidence was lower (12·2%), with prostate cancer responsible for a third of this risk (4·2%). Cervical cancer was the leading form of cancer death among women in 27 countries, followed by breast cancer (21 countries). Prostate cancer led as the most common type of cancer death in 26 countries, with liver cancer ranking second (11 countries). INTERPRETATION: The estimates indicate substantial geographical variations in the major cancers in sub-Saharan Africa. Rational cancer control planning requires capacity to be built for data production, analysis, and interpretation within the countries themselves. Cancer registries provide important information in this respect and should be prioritised for sustainable investment in the region. FUNDING: None.

Five ways to improve international comparisons of cancer survival: lessons learned from ICBP SURVMARK-2.

BACKGROUND: Comparisons of population-based cancer survival between countries are important to benchmark the overall effectiveness of cancer management. The International Cancer Benchmarking Partnership (ICBP) Survmark-2 study aims to compare survival in seven high-income countries across eight cancer sites and explore reasons for the observed differences. A critical aspect in ensuring comparability in the reported survival estimates are similarities in practice across cancer registries. While ICBP Survmark-2 has shown these differences are unlikely to explain the observed differences in cancer-specific survival between countries, it is important to keep in mind potential biases linked to registry practice and understand their likely impact. METHODS: Based on experiences gained within ICBP Survmark-2, we have developed a set of recommendations that seek to optimally harmonise cancer registry datasets to improve future benchmarking exercises. RESULTS: Our recommendations stem from considering the impact on cancer survival estimates in five key areas: (1) the completeness of the registry and the availability of registration sources; (2) the inclusion of death certification as a source of identifying cases; (3) the specification of the date of incidence; (4) the approach to handling multiple primary tumours and (5) the quality of linkage of cases to the deaths register. CONCLUSION: These recommendations seek to improve comparability whilst maintaining the opportunity to understand and act upon international variations in outcomes among cancer patients.

A way to explore the existence of "immortals" in cancer registry data - An illustration using data from ICBP SURVMARK-2.

BACKGROUND: Accurately recorded vital status of individuals is essential when estimating cancer patient survival. When deaths are ascertained by linkage with vital statistics registers, some may be missed, and such individuals will wrongly appear to be long-term survivors, and survival will be overestimated. Interval-specific relative survival that levels off above one indicates that the survival among the cancer patients is better than expected, which could be due to the presence of immortals. METHODS: We included colon cancer cases diagnosed in 1995-1999 within the 19 jurisdictions in seven countries participating in ICBP SURVMARK-2, with follow-up information available until end-2015. Interval-specific relative survival was estimated for each year following diagnosis, by country and age group at diagnosis. RESULTS: The interval-specific relative survival levels off at 1 for all countries and age groups, with two exceptions: for the age group diagnosed at age 75 years and above in Ireland, and, to a lesser extent, in New Zealand. CONCLUSION: Overall, a subset of immortals are not apparent in the early years within the ICBP SURVMARK-2 study, except for possibly in Ireland. We suggest this approach as one strategy of exploring the existence of immortals, and to be part of routine checks of cancer registry data.

Population-based cancer staging for oesophageal, gastric, and pancreatic cancer 2012-2014: International Cancer Benchmarking Partnership SurvMark-2.

Cancer stage at diagnosis is important information for management and treatment of individual patients as well as in epidemiological studies to evaluate effectiveness of health care system in managing cancer patients. Population-based studies to examine international disparities on cancer survival by stage, however, has been challenging due to the lack of international standardization on recording stage information and variation in stage completeness across regions and countries. The International Cancer Benchmarking Partnership (ICBP) previously assessed the availability and comparability of staging information for colorectal, lung, female breast and ovarian cancers. Stage conversion algorithms were developed to aggregate and map all stage information into a single staging system to allow international comparison by stage at diagnosis. In this article, we developed stage conversion algorithms for three additional cancers, namely oesophageal, gastric and pancreatic cancers. We examined all stage information available, evaluated stage completeness, applied each stage conversion algorithm, and assessed the magnitude of misclassification using data from six Canadian cancer registries (Alberta, Manitoba, Newfoundland, Nova Scotia, Prince Edward Island and Saskatchewan). In addition, we discussed five recommendations for registries to improve international cancer survival comparison by stage: (a) improve collection and completeness of staging data; (b) promote a comparable definition for stage at diagnosis; (c) promote the use of a common stage classification system; (d) record versions of staging classifications and (e) use multiple data sources for valid staging data.

Can different definitions of date of cancer incidence explain observed international variation in cancer survival? An ICBP SURVMARK-2 study.

BACKGROUND: Differences in registration practices across population-based cancer registries may contribute to international variation in survival estimates. In particular, there are variations in recorded date of incidence (DOI) as cancer registries have access to different sources of information and use different rules to determine an official DOI. This study investigates the impact of different DOI rules on cancer survival estimates. MATERIALS AND METHODS: Detailed data on dates of pathological confirmation and hospital admittance were collected from three registries participating in the ICBP SURVMARK-2 project (England, Northern Ireland and Norway). Multiple dates of incidence were determined for each cancer patient diagnosed during 2010-2014 by applying three sets of rules that prioritize either: a) histological date, b) hospital admittance date or c) the earliest date recorded. For each set of rules and registry, 1- and 5-year net survival were estimated for eight cancer sites (oesophagus, stomach, colon, rectum, liver, pancreas, lung and ovary). RESULTS: The mean difference between different DOIs within a country and cancer site ranged from 0.1-23 days. The variation in 1- and 5-year net survival using different DOIs were generally small for all registries and cancer sites. Only for liver and pancreatic cancer in Norway and ovarian cancer in England, were larger 1-year survival differences, of 2-3 % found. CONCLUSION: In the ongoing discussion of the comparability of survival estimates across registry populations, the use of different DOI definitions can be considered to have a very limited impact.

Essential TNM: Evaluation of a Training Exercise in Sub-Saharan Africa.

Information on cancer stage at diagnosis is largely missing or poorly documented among population-based cancer registries in sub-Saharan Africa (SSA). In an early field trial of Essential TNM staging, it was observed that some training was needed to enable cancer registrars to abstract the correct TNM from case records. In November 2018, the Addis Ababa City Cancer Registry hosted a training course attended by 17 participants from 16 cancer registries in SSA. The participants were asked to stage 16 cancer cases (from anonymized photocopies of case records obtained from the Global Initiative for Cancer Registry Development) before and after the training. The discrepancy of the stages from before and after were scored and compared. Results showed that there was a substantial improvement in the participants' performance after the training. The application of the Essential TNM staging system, with training in its use, would allow cancer registrars in SSA to abstract cancer stage at diagnosis in a clinically recognized format, which is crucial for cancer control and public health care policy making.

Essential TNM: a registry tool to reduce gaps in cancer staging information.

Accurate information on the extent of disease around the time of diagnosis is an important component of cancer care, in defining disease prognosis, and evaluating national and international cancer control policies. However, the collection of stage data by population-based cancer registries remains a challenge in both high-income and low and middle-income countries. We emphasise the lack of availability and comparability of staging information in many population-based cancer registries and propose Essential TNM, a simplified staging system for cancer registries when information on full Tumour, Node, Metastasis (TNM) is absent. Essential TNM aims at staging cancer in its most advanced disease form by summarising the extent of disease in the order of distant metastasis (M), regional lymph node involvement (N), and tumour size or extension, or both (T). Flowcharts and rules have been developed for coding these elements in breast, cervix, prostate, and colon cancers, and combining them into stage groups (I-IV) that correspond to those obtained by full TNM staging. Essential TNM is comparable to the Union for International Cancer Control TNM stage groups and is an alternative to providing staging information by the population-based cancer registries that complies with the objectives of the Global Initiative for Cancer Registry Development.

Survival from childhood cancers in Eastern Africa: A population-based registry study.

Cancers occurring in children in Africa are often underdiagnosed, or at best diagnosed late. As a result, survival is poor, even for cancers considered 'curable'. With limited population-level data, understanding the actual burden and survival from childhood cancers in Africa is difficult. In this study, we aimed at providing survival estimates for the most common types of cancers affecting children aged 0-14 years, in three population-based Eastern African registries; Harare, Zimbabwe (Kaposi sarcoma, Wilms tumour (WT), non-Hodgkin lymphoma (NHL), retinoblastoma, and acute lymphocytic leukaemia (ALL)), Kampala, Uganda (Burkitt lymphoma, Kaposi sarcoma, WT, and retinoblastoma), and Nairobi, Kenya (ALL, retinoblastoma, WT, Burkitt lymphoma, and Hodgkin lymphoma). We included cases diagnosed within the years 1998-2009 and followed up till the end of 2011. We estimated the observed and relative survival at 1, 3, and 5 years after diagnosis. We studied 627 individual patient records. Median follow-up ranged from 2.2 months for children with Kaposi sarcoma in Harare to 30.2 months for children with ALL in Nairobi. The proportion of children lost to follow-up was highest in the first year after diagnosis. In Harare and Kampala, the 5-year relative survival was <46% for all cancer types. The 5-year relative survival was best for children in Nairobi, though with wider confidence intervals. Survival from childhood cancers in Africa is still poor, even for cancers with good prognosis and potential for cure. Supporting cancer detection, treatment, and registration activities could help improve survival chances for children with cancers in Africa.

Three-year cancer incidence in Blantyre, Malawi (2008-2010).

In this paper, we present incidence rates of different cancers calculated for the population of Blantyre, Malawi for the period 2008-2010, using data from the Malawi Cancer Registry. Active methods were used for case finding, with standard checks for accuracy and validity performed in CanReg 4. During this 3-year period, a total of 3,711 cases were registered comprising 1,643 men (an estimated age-standardized incidence rate (ASR) of 169.8 per 100,000) and 2,068 women (ASR 238.7 per 105 ). Kaposi sarcoma (KS) was the most common cancer in men (40.5% of all cancers in men; ASR 54.0 per 105 ) while cervical cancer was the commonest in women (33.3%; ASR 88.6 per 105 ). The incidence rates for esophageal cancer remain one of the highest in the world (ASR 30.9 per 100,000 in men, 22.1 per 100,000 in women). Incidence of cancer of the prostate is relatively low in Blantyre (5.1%; ASR 16.4 per 105 ), compared with elsewhere in Africa. In childhood, the cancer spectrum is dominated by Burkitt lymphoma (32.5% ASR 90.9 per 106 ) followed by Wilms tumor (11.3%; ASR 35.9 per 106 ) and pediatric KS (11.0%; ASR 31.1 per 106 ). The overall percentage of cases with histological verification was 47.5%, a slight improvement from 42.4% in late 1990s also indicating successful case finding outside laboratories.

Long term effects of once-only flexible sigmoidoscopy screening after 17 years of follow-up: the UK Flexible Sigmoidoscopy Screening randomised controlled trial.

BACKGROUND: Colorectal cancer is the third most common cancer worldwide. Previous analyses have only reported follow-up after flexible sigmoidoscopy for a maximum of 12 years. We aimed to examine colorectal cancer incidence and mortality after a single flexible sigmoidoscopy screening and 17 years of follow-up. METHODS: In this multicentre randomised trial (UK Flexible Sigmoidoscopy Screening Trial), done between Nov 14, 1994, and March 30, 1999, 170 432 eligible men and women, who had indicated on a previous questionnaire that they would probably attend screening if invited, were randomly assigned (1:2) to an intervention group (offered flexible sigmoidoscopy screening) or a control group (not contacted). Randomisation was done centrally in blocks of 12, and stratified by trial centre, general practice, and household type. The nature of the intervention did not allow the staff to be masked to arm of the trial; however, randomisation was done in batches so that the control group and participants not yet randomised were unaware of their allocation status. The primary outcomes were incidence and mortality of colorectal cancer. Hazard ratios (HRs) and 95% CIs for colorectal cancer incidence and mortality were estimated for intention-to-treat and per-protocol analyses. The trial is registered with ISRCTN, number 28352761. FINDINGS: Our cohort analysis included 170 034 people: 112 936 in the control group and 57 098 in the intervention group, 40 621 (71%) of whom were screened and 16 477 (29%) were not screened. During screening and a median of 17·1 years' follow-up, colorectal cancer was diagnosed in 1230 individuals in the intervention group and 3253 in the control group, and 353 individuals in the intervention group versus 996 individuals in the control group died from colorectal cancer. In intention-to-treat analyses, colorectal cancer incidence was reduced by 26% (HR 0·74 [95% CI 0·70-0·80]; p<0·0001) in the intervention group versus the control group and colorectal cancer mortality was reduced by 30% (0·70 [0·62-0·79]; p<0·0001) in the intervention group versus the control group. In per-protocol analyses, adjusted for non-compliance, colorectal cancer incidence and mortality were 35% (HR 0·65 [95% CI 0·59-0·71]) and 41% (0·59 [0·49-0·70]) lower in the screened group. INTERPRETATION: A single flexible sigmoidoscopy continues to provide substantial protection from colorectal cancer diagnosis and death, with protection lasting at least 17 years. FUNDING: National Institute for Health Research Efficacy and Mechanism Evaluation.

Uganda experience-Using cost assessment of an established registry to project resources required to expand cancer registration.

BACKGROUND: The objectives of this study are (1) to estimate the cost of operating the Kampala Cancer Registry (KCR) and (2) to use cost data from the KCR to project the resource needs and cost of expanding and sustaining cancer registration in Uganda, focusing on the recently established Gulu Cancer Registry (GCR) in rural Northern Uganda. METHODS: We used Centers for Disease Control and Prevention's (CDC's) International Registry Costing Tool (IntRegCosting Tool) to estimate the KCR's activity-based cost for 2014. We grouped the registry activities into fixed cost, variable core cost, and variable other cost activities. After a comparison KCR and GCR characteristics, we used the cost of the KCR to project the likely ongoing costs for the new GCR. RESULTS: The KCR incurred 42% of its expenditures in fixed cost activities, 40% for variable core cost activities, and the remaining 18% for variable other cost activities. The total cost per case registered was 28,201 Ugandan shillings (approximately US $10 in 2014) to collect and report cases using a combination of passive and active cancer data collection approaches. The GCR performs only active data collection, and covers a much larger area, but serves a smaller population compared to the KCR. CONCLUSION: After identifying many differences between KCR and GCR that could potentially affect the cost of registration, our best estimate is that the GCR, though newer and in a rural area, should require fewer resources than the KCR to sustain operations as a stand-alone entity. The optimal structure of the GCR needs to be determined in the future.

Resource requirements for cancer registration in areas with limited resources: Analysis of cost data from four low- and middle-income countries.

BACKGROUND: The key aims of this study were to identify sources of support for cancer registry activities, to quantify resource use and estimate costs to operate registries in low- and middle-income countries (LMIC) at different stages of development across three continents. METHODS: Using the Centers for Disease Control and Prevention's (CDC's) International Registry Costing Tool (IntRegCosting Tool), cost and resource use data were collected from eight population-based cancer registries, including one in a low-income country (Uganda [Kampala)]), two in lower to middle-income countries (Kenya [Nairobi] and India [Mumbai]), and five in an upper to middle-income country (Colombia [Pasto, Barranquilla, Bucaramanga, Manizales and Cali cancer registries]). RESULTS: Host institution contributions accounted for 30%-70% of total investment in cancer registry activities. Cancer registration involves substantial fixed cost and labor. Labor accounts for more than 50% of all expenditures across all registries. The cost per cancer case registered in low-income and lower-middle-income countries ranged from US $3.77 to US $15.62 (United States dollars). In Colombia, an upper to middle-income country, the cost per case registered ranged from US $41.28 to US $113.39. Registries serving large populations (over 15 million inhabitants) had a lower cost per inhabitant (less than US $0.01 in Mumbai, India) than registries serving small populations (under 500,000 inhabitants) [US $0.22] in Pasto, Colombia. CONCLUSION: This study estimates the total cost and resources used for cancer registration across several countries in the limited-resource setting, and provides cancer registration stakeholders and registries with opportunities to identify cost savings and efficiency improvements. Our results suggest that cancer registration involve substantial fixed costs and labor, and that partnership with other institutions is critical for the operation and sustainability of cancer registries in limited resource settings. Although we included registries from a variety of limited-resource areas, information from eight registries in four countries may not be large enough to capture all the potential differences among the registries in limited-resource settings.

Population Attributable and Preventable Fractions: Cancer Risk Factor Surveillance, and Cancer Policy Projection.

The proportions of new cancer cases and deaths that are caused by exposure to risk factors and that could be prevented are key statistics for public health policy and planning. This paper summarizes the methodologies for estimating, challenges in the analysis of, and utility of, population attributable and preventable fractions for cancers caused by major risk factors such as tobacco smoking, dietary factors, high body fat, physical inactivity, alcohol consumption, infectious agents, occupational exposure, air pollution, sun exposure, and insufficient breastfeeding. For population attributable and preventable fractions, evidence of a causal relationship between a risk factor and cancer, outcome (such as incidence and mortality), exposure distribution, relative risk, theoretical-minimum-risk, and counterfactual scenarios need to be clearly defined and congruent. Despite limitations of the methodology and the data used for estimations, the population attributable and preventable fractions are a useful tool for public health policy and planning.

Black-white differences in cancer risk in Harare, Zimbabwe, during 1991-2010.

Data from 20 years of cancer registration in Harare (Zimbabwe) are used to investigate the risk of cancer in the white population of the city (of European origin), relative to that in blacks (of African origin). In the absence of information on the respective populations-at-risk, we calculated odds of each major cancer among all cancers, and took the odds ratios of whites to blacks. Some major differences reflect obvious phenotypic differences (the very high incidence of skin cancer-melanoma and nonmelanoma--in the white population), whereas others (high rates of liver cancer, Kaposi sarcoma and conjunctival cancers in blacks) are the result of differences in exposure to infectious agents. Of particular interest are cancers related to lifestyle factors, and how the differences in risk are changing over time, as a result of evolving lifestyles. Thus, the high risk of cancers of the esophagus and cervix uteri in blacks (relative to whites) and colorectal cancers in whites show little change over time. Conversely, the odds of breast cancer, on average four times higher in whites than blacks, has shown a significant decrease in the differential over time. Cancer of the prostate, with the odds initially (1991-1997) 15% higher in whites had become 33% higher in blacks by 2004-2010.

Tumor size and stage of breast cancer in Côte d'Ivoire and Republic of Congo - Results from population-based cancer registries.

PURPOSE: Breast cancer is now the leading female cancer in sub-Saharan Africa, but there is relatively little information on breast cancer characteristics from this region. We studied, on a population basis, the size and stage of female breast cancer at diagnosis in Côte d'Ivoire and Republic of Congo. METHODS: Data on tumor size and stage of breast cancer at diagnosis were collected by population-based cancer registries in Abidjan (the capital of Côte d'Ivoire; 141 cases) and Brazzaville (the capital of Republic of Congo; 139 cases) from a random group of female breast cancer cases that were diagnosed in 2008-2009 using the same protocol. RESULTS: The majority of breast cancers in both countries were advanced cancers. In Côte d'Ivoire, 68% of tumors were ≥5 cm in diameter and 74% of cancers were stage III or IV at diagnosis; the corresponding proportions in Republic of Congo were 63% and 81%. CONCLUSION: These results underscore the importance of increased awareness about early detection of breast cancer, as well as expansion of the capacity to provide appropriate diagnosis, treatment, and palliative care in sub-Saharan Africa.

Cancer registries in Africa 2014: A survey of operational features and uses in cancer control planning.

A questionnaire survey of all active population based cancer registries in sub-Saharan Africa obtained information on their characteristics (size, staffing, funding), methods of working, the nature of any links between registries and their respective Health Authorities (national and/or local), and the use of their data in research or cancer control planning. 23/25 registries (92%) responded. Sources of direct funding and estimated amounts from each source were established, and suggest that it is approximately US$8-9 per case registered. Almost half of the funding is used for routine data collection, processing and analysis. Staffing levels vary, partly as a function of the registry size (approximately one FTE per 300 cases registered). Most data collection is active, using multiple sources (median 10 per registry), and is largely paper-based (abstraction onto paper forms), although all use the computer system CanReg© for data entry, storage and analysis. Most reporting by the registries is remarkably timely, and in general, their results are widely used by health authorities and other stakeholders in planning and evaluating services, while research output is much more variable. These registries are the source of almost all the existing information on cancer incidence and mortality in sub-Saharan Africa, as published in IARC's "Globocan".

Trends in cancer incidence in rural Eastern Cape Province; South Africa, 1998-2012.

There are few cancer trend data reported in sub-Saharan Africa notably due to the scarcity of population-based cancer registries (PBCRs). The Eastern Cape Province PBCR is amongst the few registries in sub-Saharan Africa that reports data for a rural population. Trends in cancer incidence are reported for the period 1998-2012. Registered cases, age-standardized rates (ASRs) and standardized rate ratios are presented for the most common cancers in both males and females in three periods (1998-2002, 2003-2007 and 2008-2012). In males, the most commonly diagnosed cancer during the 15 year period was cancer of the oesophagus; incidence rates showed a significant decline over the 15 year period, entirely due to a 30% decrease between 2003-2007 and 2008-2012, to an ASR of 23.2 per 100,000 population. This was followed by prostate cancer, the incidence of which was more than doubled to a level of 9.9/100,000. In women, cancer of the cervix uteri has become the most common malignancy, with a significant increase in incidence during the period to 29.0/100,000. Oesophageal cancer is second in frequency, with (as in males) a significant decline in the final 10 years to an incidence of 14.5/100,000 in 2008-2012. The incidence of breast cancer increased by 61%, although the absolute rate remains low (12.2/100,000). The incidence rates of colorectal cancer are low, and the increases in incidence, although relatively large (35% in men, 63% in women) were not statistically significant. Kaposi sarcoma showed a dramatic increase in incidence in both sexes (3.5-fold in men, 11-fold in women) although the incidence remains relatively low by southern African standards. Cancer prevention and control activities in the area need to be informed by these data and strengthened.

Cancer in Africa 2012.

BACKGROUND: Noncommunicable diseases, and especially cancers, are recognized as an increasing problem for low and middle income countries. Effective control programs require adequate information on the size, nature, and evolution of the health problem that they pose. METHODS: We present estimates of the incidence and mortality of cancer in Africa in 2012, derived from "GLOBOCAN 2012," published by the International Agency for Research on Cancer. RESULTS: There were 847,000 new cancer cases (6% of the world total) and 591,000 deaths (7.2% of the world total) in the 54 countries of Africa in 2012, with about three quarters in the 47 countries of Sub-Saharan Africa. While the cancer profiles often differ markedly between regions, the most common cancers in men were prostate (16.4% of new cancers), liver (10.7%), and Kaposi sarcoma (6.7%); in women, by far the most important are cancers of the breast (27.6% of all cancers) and cervix uteri (20.4%). CONCLUSIONS: There are still deficiencies in surveillance systems, particularly in Sub-Saharan Africa and, specifically, of their most vital component, population-based cancer registries. With the number of annual cancer cases and deaths likely to increase by at least 70% by 2030, there is a pressing need for a coordinated approach to improving the extent and quality of services for cancer control in Africa, and better surveillance systems with which they can be planned and monitored. IMPACT: The results are the best data currently available and provide a reasonable appraisal of the cancer situation in Africa.

Global burden of cancer in 2008: a systematic analysis of disability-adjusted life-years in 12 world regions.

BACKGROUND: Country comparisons that consider the effect of fatal and non-fatal disease outcomes are needed for health-care planning. We calculated disability-adjusted life-years (DALYs) to estimate the global burden of cancer in 2008. METHODS: We used population-based data, mostly from cancer registries, for incidence, mortality, life expectancy, disease duration, and age at onset and death, alongside proportions of patients who were treated and living with sequelae or regarded as cured, to calculate years of life lost (YLLs) and years lived with disability (YLDs). We used YLLs and YLDs to derive DALYs for 27 sites of cancers in 184 countries in 12 world regions. Estimates were grouped into four categories based on a country's human development index (HDI). We applied zero discounting and uniform age weighting, and age-standardised rates to enable cross-country and regional comparisons. FINDINGS: Worldwide, an estimated 169·3 million years of healthy life were lost because of cancer in 2008. Colorectal, lung, breast, and prostate cancers were the main contributors to total DALYs in most world regions and caused 18-50% of the total cancer burden. We estimated an additional burden of 25% from infection-related cancers (liver, stomach, and cervical) in sub-Saharan Africa, and 27% in eastern Asia. We noted substantial global differences in the cancer profile of DALYs by country and region; however, YLLs were the most important component of DALYs in all countries and for all cancers, and contributed to more than 90% of the total burden. Nonetheless, low-resource settings had consistently higher YLLs (as a proportion of total DALYs) than did high-resource settings. INTERPRETATION: Age-adjusted DALYs lost from cancer are substantial, irrespective of world region. The consistently larger proportions of YLLs in low HDI than in high HDI countries indicate substantial inequalities in prognosis after diagnosis, related to degree of human development. Therefore, radical improvement in cancer care is needed in low-resource countries. FUNDING: Dutch Scientific Society, Erasmus University Rotterdam, and International Agency for research on Cancer.