Health Research, Vol. 3, Issue 3, Sep  2019, Pages 23-31; DOI: 10.31058/j.hr.2019.33003 10.31058/j.hr.2019.33003

Examining Cancer Prevalence in Africa

, Vol. 3, Issue 3, Sep  2019, Pages 23-31.

DOI: 10.31058/j.hr.2019.33003

İlker Etikan 1* , Ogunjesa Babatope 1

1 Biostatistics Department, Faculty of Medicine, Near East University, Nicosia, Turkey

Received: 26 November 2019; Accepted: 29 November 2019; Published: 30 November 2019

Abstract

Cancer is one of the major contributors to the global disease burden with a devastating effect on the socio-economic status of any nation. In Africa countries, the rising number of new cases of cancer and the geographical disproportionate pattern has become a challenge to the continent’s public healthcare system. Thus, the study seeks to investigate the trend of cancer on the continent by reviewing previous works of literature and by examining the challenges surrounding the scourge of this disease. Inference from the study shows that for effective combat against cancer, different countries on the continent need to commit sufficient resources to cancer care and encourage early screening procedures in order to reduce the late presentation of the diseases which is often the case in many African countries.

Keywords

Africa, Cancer, Carcinogen, Mortality, Non-Communicable Diseases, Survival

1. Introduction

The non-communicable diseases (NCDs) have been a major contributor to the record of global disease burden and human fatality. The World Health Organization (WHO) reported an annual death of about 41 million people which accounts for 71% of deaths of all deaths recorded worldwide [1]. Within the age bracket of 30-69 years old, 15 million individuals died in this age cohort as a result of NCDs. In the low-income countries, about 32 million of deaths in these regions of the world are attributed to NCDs.

Cancer is a disease that occurs as a result of abnormal growth and division of body cells which results in malignant tissue growth in any region of the body. This abnormal cell growth and division continue to attack and spread to other healthy regions of the body resulting in other disease comorbidities. Cancerous cells are said to occur in the body due to genetic material interactions with other carcinogens. Carcinogen substances could be physical, chemical or biological in nature. Examples of physical carcinogens are ionization radiations, ultraviolet rays, glass wool, Erionite, metallic alloys factors [2,3]. Chemical carcinogens include arsenic, tobacco constituents, pesticides, and other synthetic chemical compounds while infections as a result of viruses or bacteria are examples of biological carcinogens [4]. Tobacco Smoking, alcohol consumption and other nutritional deficiencies are also considered as a lifestyle factor that increases the risk of cancer development.

Cancer is a major example of NCDs only coming second after cardiovascular diseases (CVDs). CVDs are linked to 17.9 million deaths while cancer is responsible for 9 million fatalities followed by respiratory infections and diabetes with a figure of 3.9 million and 1.6 million deaths respectively. These aforementioned categories of diseases are reckoned to have caused more than 80% of untimely deaths with ties to NCDs. Most often, cancer is named after the region of occurrence in the body. Thus, we have cancers such as lung cancer, stomach cancer, cervical cancer, breast cancer and so on.

Cancer is a global disease burden that has continues to be on an increasing trend for the past two decades [5]. The increasing incidence and deaths from cancer have become so pronounced in both low and middle-income countries in recent times as a result of risk factors stemming from changing lifestyle behavior and environmental impacting factors [6]. The 2012 statistics record for new cases of cancer was 14.1 million with 8.2 million cancer deaths globally. By 2030, the prevalence of cancer is expected to rise to about 75 million cases while incidence cases and projected mortality are expected to reach 27 million and 17 million cancer cases respectively [7].

The global incidence of cancer in 2018 is 18.1 million with a mortality figure of 9.6 million people as shown in Table 1. The cancer incidence rate among males is 9.5 million and 8.6 million among the female gender. According to the 2018 WHO cancer statistics, there are 2.09 million cases of lung cancer, 2.09 million cases of breast cancer, 1.8 million cases of colorectal cancer and 1.03 million cases of stomach cancer. Lung cancer resulted in the deaths of 1.76 million people, colorectal cancer into 862,000 deaths and breast cancer into 627,000 deaths [1].

A 70% increment in cancer incidence has been predicted to occur in the next 20 years. Globally, one in every six women and one in every five men are known to have a cancer problem in their life course. And also for every six deaths, cancer is reported to have caused the death of an individual. For every eight men with cancer, one died and for every eleven women with this disease, one died and about 70% of deaths linked to cancer occur in the developing nations. The economic loss attributed to the burden of cancer in 2010 was about US$ 1.16 trillion.

Table 1. 2018 World Summary Statistics of Cancer Record [8].

Males

Females

Both Sexes

Population

3,850,719,287

3, 782,099,828

7,632,819,272

Number of new cancer cases

9,456,418

8,622,539

18,078,957

Age-standardized incidence rate(World)

218.6

182.6

197.9

Risk of developing cancer before the age of 75 years (%)

22.4

18.3

20.2

Number of cancer deaths

5,385,640

4,169,387

9,555,027

Age-standardized mortality rate(World)

122.7

83.1

101.1

Risk of dying from cancer before the age of 75 years (%)

12.7

8.7

10.6

5-year prevalent cases

21, 014,830

22,826,472

43,841,302

Top 5 most frequent cancers excluding non-melanoma skin cancer

Lung

Prostate

Colorectum

Stomach

Liver

Breast

Colorectum

Lung

Cervix uteri

Thyroid

Lung

Breast

Colorectum

Prostate

Stomach

In terms of geographical variation, the increasing burden of cancer is evidenced in low-income and middle-income countries (LMICs), as a result of weak healthcare systems and other pathological service deliveries that can ensure a quick diagnosis of cancer that preludes other necessary palliative measures. This is in contrast with the developed nations with easy accessibility to cancer care and support.

2. The Outlook of Cancer in Africa

Many countries in the Africa continent are in the list of the LMICs. Thus, African countries are more vulnerable to the incidence of diseases and several other public health challenges mostly as a result of endemic poverty and a poor healthcare system that characterizes this region of the world. The African continent makes up 17.7 % of the world population and the second-largest and second-most-populous continent in the world with an estimate of 1.3 billion inhabitants [9]. The 2018 population growth rate was 2.55% and about 41% of the population is below 15 years. The life expectancy of the inhabitants of the continent is 52 years in stark contrast with is obtained in richer countries.

Like other types of NCDs, the incidence of cancer in Africa has attracted the attention of many health experts and stakeholders in the public and private health sector [10]. For the year 2018 end, the incidence of cancer in Africa is 1,055,172 cases with a 5 years’ prevalence of 1,930,912 cases. There is a disparity in the incidence of cancer cases on the continent. More cancer cases were recorded among the female gender with an incidence record rate of 608,616 and 446,556 cases among males. The risk of developing cancer before the age of 75 years is higher among the female population (12.7%) in contrast to the male population (14.1%). In 2018, the number of deaths as a result of cancer was 693,487 out of which 316,531(45.64%) occurred among the male population and 376,956(54.36%) in the female population. The risk of dying of cancer before the age of 75 years varies across the gender category. The female has a higher risk of dying (9.6%) when compared with the male population with a 9.2% risk.

As a result of the increasing incidence of cancer in Africa, more challenges are posed to the socio and economic growth and development of the continent especially in the sub-Sahara Africa region. [10] posited in their study that the burden of cancer is prevalent among younger women than older women. Thus, the implication of this suggested that the sector of the economy where women are quite very active such as agriculture will be affected which could further worsen the problem of hunger and slow growth in Africa. The maternal health also is at risk affecting the child survival profile of the African children that are already in a gory state especially in sub-Saharan Africa [11,12].

3. Common Cancer Cases in Africa

There are different types of cancer and often named based on their site of occurrence in the body. Breast cancer, cervix uteri, prostate cancer, liver cancer, and colorectum cancer are the most prevalent causes of cancer in Africa. Among the female population, breast cancer is the most prevalent cancer occurrence while prostate cancer is more prevalent in the male population as indicated by Figure 1 and Figure 2.

Figure 1. The Incidence Rates of Cancer types in Africa according to gender for 2018 [8].

Figure 2. The Incidence and Mortality Rate of top cancer cases in Africa for 2018 [8].

3.1. Breast Cancer

Breast cancer is the second common most diagnosed cancer in the World and also the most common type on the Africa continent. In 2012, the estimated breast cancer incidence was 1.7 million cases and 521,900 deaths in contrast to 2.08 million incidence cases and 626,679 deaths in 2018 [8,13]. Globally, breast cancer accounts for 11.6% of all different types of cancer diagnosed. African global share of the new cases of breast cancer is 8.1 % coming behind Asia (43.6%), Europe (25.0%), North America (12.6%) and the Latin American and Caribbean (9.6%). In terms of fatality, the African continent is responsible for 11.8 % of the global death attributable to breast cancer coming after the Asia region (49.6%) and the European region (22.0%).

Table 2. Incidence and Mortality of Breast Cancer in Africa.

Regions

Incidence

Mortality

New Cases

Cumulative Risk (%) (0-74yrs)

Death Cases

Cumulative Risk (%) (0-74yrs)

East Africa

40,310

3.15%

20,165

1.62%

Middle Africa

14,486

2.86%

7,864

1.64%

North Africa

53,917

5.06%

20,058

1.96%

Southern Africa

14,820

4.93%

5,002

1.60%

Western Africa

45,157

3.92%

20,983

1.92%

Breast cancer makes up 16.0 % of all the cancer types diagnosed on the continent. The 2018 incidence cases due to breast cancer in Africa are 168,890 and 74,072 mortality cases. There is a geographical variation in new cases of breast cancer on the continent ( Table 2 ). There are more new cases of breast cancer (53,917) reported in the Northern Africa region making the region the topmost breast cancer zone on the continent. This is closely followed by the Western African Region with 45,157 new cases. The East Africa region is the third-ranked region with 40,310 incidence cases. The Middle Africa region and the Southern Africa region reported 14,486 and 14,820 incidence cases respectively.

3.2. Cervical Cancer

Cervical cancer remains one of the deadliest cancers ravaging the female population. Many previous studies have linked the occurrence of cervical cancer with the human papillomavirus (HPV) infection. According to these scientific studies, the carcinogenic attributes of the HPV though not in all entirety are considered catalysts for the incidence of cervical cancer [14,15].

Cervical cancer comorbidity with other diseases such as HIV/AIDs makes the disease deadlier. Among women that are HIV positive, cervical cancer is the most common cancer occurrence. HIV positive women are about four to five times at risk of cervical cancer in contrast to HIV negative women. Likewise, women are twice the risk of contracting an HIV infection when they are suffering from HPV infection. Over 80% of incidence and mortality cases of cervical cancer emanate from developing countries and about 500,000 women globally are affected annually.

Worldwide, the incidence of cervical cancer for 2018 was 18,078,957 cases making it 3.2% of all cancer cases reported. In Africa, it is the second most common cancer occurrence on the continent. The 2018 new cases of cervical cancer are 119,284 (11.3%) out of the 1,055,172 new cancer cases and the number one killer cancer on the continent. Among the female population in Africa, cervical cancer is the second most cancer and responsible for the most morbidity and mortality cases in the sub-Saharan where they are extremely prevalent. West Africa and the East Africa regions have the highest new cases and mortality cases of cervical cancer in Africa indicating there are disparities in cervical cancer on the continent ( Table 3 ).

Table 3. Incidence and Mortality of Cervical Cancer in Africa [8].

Regions

Incidence

Mortality

New Cases

Cumulative Risk (%)(0-74yrs)

Death Cases

Cumulative Risk (%)(0-74yrs)

East Africa

52,633

4.34%

37,017

3.42%

Middle Africa

12,635

3.02%

9,418

2.49%

North Africa

7,625

0.82%

5,243

0.62%

Southern Africa

14,409

4.20%

6,480

2.07%

Western Africa

31,955

3.47%

23,529

2.79%

Cervical cancers just like other examples of cancer are not quickly diagnosed or treated until the very advanced manifestation in several African regions as a result of the poor reproductive healthcare system. Pap smear screening alternative called a cytology process is a method commonly used in cervical cancer diagnosing. This method is widely being adopted in many developed and high resource countries in the world preventing about 80% occurrence of cervical cancer but their usage and coverage are quite still low in Africa [16,17]. In the sub-Sahara region of Africa, [18] reported the absence of cervical cancer screening programs in many countries, and in the place where it exists; the coverage is quite low in proportion to women at risk of the diseases. For instance, it was reported that in Uganda, cervical screening for the population ranges from 4.8% to 30% [19].

3.3. Prostate Cancer

Prostate cancer (PCa) is the third prevalent and eight ranked death-causing cancer disease in the world. The risk factors linked to PCa include socio-demographic factors such as age, race and some other genetic factors. Pca is associated with the male population and it is a considerable public health issue as regards to men’s health and the public health in general [5]. Even though studies from [20] and [21] have indicated that PCa is most common among the African American men, this view was expected to be mirrored among the Western African men due to a genetic ancestral link between the two, but this assertion is still considered indecisive [22].

According to the [8] study, there are 1,276,106 new million cases of Pca with a 5-year prevalence record of 3,727,658 million cases. Pca in 2018 was responsible for 358,989 deaths cases in the world. In Africa, Pca is the third most common cancer with 80,971 new cases (7.70%) and fourth cancer cause of deaths resulting in 42,298 deaths (6.10%) with a 5-year prevalence figure of 131,423 cases. The high incidence of Pca was more prevalent in the Western African followed by the Eastern African and Northern Africa being the region with the lowest incidence of Pca ( Table 4 ).

Table 4. Incidence and Mortality of Prostate Cancer in Africa [8].

Regions

Incidence

Mortality

New Cases

Cumulative Risk(%)(0-74yrs)

Death Cases

Cumulative Risk (%)(0-74yrs)

East Africa

20,816

2.74%

12,790

1.37%

Middle Africa

11,666

4.07%

7,133

2.13%

North Africa

11,770

1.45%

5,148

0.23%

Southern Africa

12,950

7.04%

4,699

2.07%

Western Africa

23,769

3.72%

12,528

1.77%

4. Challenges on African Cancer Status

Generally, the problem of cancer in Africa is multifaceted. One of the major problems is in the area of medical record keeping. Many of the healthcare facilities are ill-equipped with modern-day technologies that facilitate easy data recording and management across different platforms. This inadequacy has greatly impaired information availability necessary for effective assessment of the actual state of many health conditions and health services on the continent [23]. The effect of poor record-keeping just like on other diseases is also reflected in cancer data. Only a quite number of cancer registries are present on the continent for cancer data collation and most of which are not in consonance with global practice in providing an up to date record on the state of cancer [6,24].

Aside from the data management challenge which might have resulted in many underreported cases of cancer, awareness about cancer diseases especially in many rural communities are not well pronounced in contrast to other health conditions such as malaria and HIV/AIDs. Hence, the late presentation of this cancer disease is common in Africa thus resulting in a low survival rate for many cancer patients. This assertion was further corroborated by a study that seeks to examine 1.2 million cancer patients in a Kampala registry in Uganda. The study found that over a five-year period, the absolute survival of women in Uganda was 15.90% and relative survival of 18.2% which is far below the survival of African-American women having an estimated 60% survival rate [25]. In a similar vein in Zimbabwe, between 1993 to 1997 period, the 5-year absolute and relative survival values for diagnosed cancer patients were found to be 26.5% and 30.50% respectively in contrast to about 60% for their African-American counterpart within the same timeline [25].

Medical treatment for cancer is another daunting task for an average cancer patient in most African countries. In most countries with high economic index, cancer care is subsidized by governments which made these treatment procedures affordable for cancer patients. However, in Africa, it has been reported that expenses on cancer treatment are more than the average household income of an African family [26]. Hence, in many cases, such treatment care and support are beyond the reach of an average African family.

In conclusion, it is suggested that different levels of governments of countries in Africa must give cancer the necessary attention it deserves. There is a need for more funding into cancer prevention, cure, and management. There is a need to adequately equip the different healthcare facilities that cater to cancer care in countries in Africa. National Cancer Research institutes of various countries in Africa need to form a strong partnership and cross idea-sharing culture which is capable of reducing the incidence of cancer on the continent. Governments on the continent should also support trado-medical research as seen lately in India and China in order to complement the effort of clinical research in identifying the management and cure for cancer. There is also a need to speed up the early diagnosis of cancer which can be achieved by conducting sensitization programs and localizing screening processes starting from the grassroots communities to the urban centers.

Conflicts of Interest

The authors declare that there is no conflict of interest regarding the publication of this article.

Acknowledgments

The authors would like to acknowledge the research team of the GLOBOCAN which worked painstakingly in order to make statistics about Cancer cases available.

Copyright

© 2017 by the authors. Licensee International Technology and Science Press Limited. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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