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HomeA FocusExperts call for comprehensive, large-scale response to slash Africa's cancer burden

Experts call for comprehensive, large-scale response to slash Africa's cancer burden

Cancer mortality rates in sub-Saharan Africa – one of the top three causes of premature deaths in most countries in the region – are set to double by 2030, prompting a call by researchers for a large-scale response focusing on consistent supply of drugs, training of oncology staff and broader access to treatment.

Similarly, in another study in South Africa, researchers have called for a comprehensive National Cancer Control Plan to address the burden of cancer, writes MedicalBrief.

In findings published in the South African Medical Journal, Wits University researchers say cancer mortality rates in South Africa have increased since 1997, regardless of gender, but the disease killed more men than women, the most common cause being lung cancer, while cancer of the cervix topped women’s deaths, according to a recent study.

The researchers found that overall, there was a decline in years of potential productive life lost (YPPLL) for cancer in the young population, but this increased in older people.

They said that as the burden of cancer is increasing, some studies have emphasised the importance of dealing with numerous facets of the disease’s epidemiology, prevention, treatment and research.

However, the costs of adequate treatments are progressively becoming unsustainable, even for developed countries.

Cancer control must, therefore, focus on action against the main risk factors, including tobacco use, alcohol consumption, obesity and lack of physical activity, excessive exposure to sunlight, radiation, infectious agents, and chemicals in food and the environment, they suggested, but this would need adequate policies, proper implementation and continued monitoring, all supported by a comprehensive National Cancer Control Plan.

In an effort to limit the risk of malignant disease, the Tobacco Products Control Act, Liquor Act, hepatitis B vaccination programme, cervical cancer screening programme and vaccination programme against human papillomavirus had all been implemented in SA, but the mortality trends from all cancers have never been well investigated.

To this purpose, the researchers examined the trends in mortality for all cancers in SA from 1997-2016.

Their study was based on data from StatsSA, and they noted a significant difference in the number of cancer deaths by gender, with 51.1% of males and 48.9% of females dying from the disease.

These numbers proportionally increased in males from between 10 and 64-years-old, but in women, increased between 10 and 69.

While the number of cancer deaths declined after women reached their 70s, cases peaked at the age of ≥85 years, at 12.3%, a figure supported by the fact that women have higher life expectancy than men in this country.

The adequate control of infectious diseases, like antiretroviral therapy among HIV-positive patients, had also increased life expectancy in SA, leading to high incidence and mortality for chronic diseases, including cancer.

Strengths and limitations

The period 1997-2016 has high data completeness. StatsSA is one of the primary data sources of cancer statistics, with representative information on mortality patterns in the country, enabling the researchers to understand the direction and magnitude of the cancer epidemic as well as formulation of more focused public health interventions.

A limitation was that this study only included the cancer deaths recorded on death certificates. It is possible that some patients may not attend hospitals; hence there might be no ongoing care-seeking, and they would not be included in this study.

In addition, some patients might seek help from traditional healers, for instance, and it might not be possible to capture information from them, which could cause bias in the recruitment of cancer deaths.

There is also a lack of data on cancer staging, making it difficult to report indices based on stages of malignancies.

In the same vein, Health Policy Watch reports that although Africa has one of the highest cancer death rates in the world, statistics could be slashed if the continent had more access to treatments that are widely available in high-income countries for the biggest killers – breast, cervical, lung and prostate cancers and Kaposi sarcoma – and if basic care levels were stepped up.

A recent study by the Botswana-Rutgers Partnership for Health, which researched which treatments that are effective in other regions could have an impact in sub-Saharan Africa (SSA) – but are not available or hard to get – confirmed that cancer is in the top three causes of premature death in most countries in SSA.

These are projected to nearly double between 2020 and 2030, reaching about 1m by 2030.

The report adds that in SSA “basic levels of cancer care, treatment and palliation are limited”, with patients having “poor survival outcomes across most malignancies”.

Access to treatments

“Cancer is threatening sub-Saharan African populations to a degree that demands a large-scale response,” said Richard Marlink, director of Rutgers Global Health Institute and a study author.

“This guidance provides a framework for how to improve access to life-saving medications … the high-impact treatments available elsewhere are needed in this region.”

Cervical cancer

Cervical cancer is the leading cause of cancer-related death in women in SSA, with standard of care being chemotherapy in conjunction with radiation therapy.

But a study of 29 oncology treatment centres in 12 SSA countries found an inconsistent supply of cisplatin, a preferred chemotherapy drug, as well as limited access to radiation.

Plus, access to radiotherapy is limited because of a lack of trained staff and equipment and equipment maintenance.

In Harare, there has been a 4.9% average annual increase in breast cancer and a 4.5% increase in Uganda.

Mortality rates in southern Africa are “among the world’s highest, due to late-stage presentation and lack of screening programmes”, said the study, which was published in PLOS Global Public Health.

In a population-based registry study of 834 patients in 11 countries in SSA, only one-third received chemotherapy.

Breast cancer patients are also not routinely tested to determine their specific hormonal profiles, and “treatment …greatly differs based on hormonal status and human epidermal growth factor (HER2) expression status”, the study reported.

HER2-positive breast cancer is one that tests positive for the protein HER2, which promotes the growth of cancer cells. Treatments that specifically target HER2 are very effective.

Hormonal therapy with tamoxifen is recommended for HER2 tumours and is inexpensive or even free in some countries, so it may be prescribed even if hormonal profiling has not taken place. This could harm the patient and provide no therapeutic advantage.

But even when hormonal profiling is available, medications that have proved to be most effective “may be cost-prohibitive” – like trastuzumab, which targets HER2.

Prostate cancer

A leading cause of cancer death among men is prostate cancer, particularly in southern Africa, with some 66 cases per 100 000 (more than double the rate of West and East Africa).

Surgical castration to remove the testicles is widespread in SSA, yet “newer generation oral hormone therapy may have an expanded role”.

Abiraterone with prednisone therapy is an oral hormone therapy that can improve outcomes and is included on the WHO’s Essential Medicines List, “expected to be available through multiple generic options with reduced pricing in the future”.

Kaposi sarcoma

While Kaposi sarcoma (KS) is relatively rare worldwide, it is more common in people with weakened immune systems and has increased 20-fold in SSA since the 1980s, with the HIV/Aids epidemic.

Antiretroviral treatment has reduced Aids-associated KS, but there is still “ongoing significant morbidity and mortality”.

Since most cases are associated with HIV, “it is imperative for all patients living with HIV to receive antiretroviral therapy”.

Paclitaxel can be used to treat advanced KS and is “more affordable and readily available in SSA” than other medicines.

WHO’s updated Essential Medicines List (EML) includes a new KS treatment, liposomal doxorubicin.

The study also notes the lack of interest in studying new therapies for KS, despite the significant burden of disease in the region.

Lung cancer

In high-income countries, molecular targeted therapies for lung cancer have achieved substantial survival benefits, but SSA lacks equipment and trained personnel for this.

Increased affordability and the marketing of tobacco products is expected to this cancer, and the researchers emphasised the need for more advanced pathology capabilities to improve diagnostics and therapeutics.

“High costs are a major challenge to bridging the stark inequities in access to treatments,”  said lead author Kirthana Sharma.

“Diagnostic and laboratory infrastructure also need to be strengthened, and the oncology workforce must be further trained and developed.”

The Botswana-Rutgers Partnership for Health is a collaboration between Botswana’s Ministry of Health, the University of Botswana and Rutgers Global Health Institute.

Botswana’s cancer mortality rate exceeds 63%, and the partnership is engaged in efforts to strengthen the country’s health systems and provide comprehensive oncology care.

Study details

Cancer mortality trends in South Africa: 1997-2016

M Nhleko, I Edoka, E Musenge.

Published in the SA Medical Journal in August 2023

Background
Upon the addition of the numbers corresponding to various cancer anatomical locations in the report published by Statistics South Africa (StatsSA), the absolute number and proportion of deaths due to all cancers increased from 36 726 (8.0%) in 2013 to 40 460 (8.5%) in 2015. These high figures suggest that malignant neoplasms were in fact the second-most frequent cause of death in South Africa (SA) in 2013, and moved to the first rank in 2015.

Objectives
To support the initiative aimed at reducing cancer mortality in SA. To this purpose, we assessed trends in cancer mortality rates among males and females in SA from 1997 to 2016 to better understand the increasing threat of cancer mortality in SA.

Methods
The general mortality data for the period 1997 – 2016, as captured from death certificates in SA, was retrieved from StatsSA. Age-standardised mortality rates (ASMR) for each year were computed using the world standard population structure proposed by Segi as the reference population. The adjusted rates were reported per 100 000 population per year. The years of potential productive life lost (YPPLL) due to cancer deaths were calculated for each age group and gender.

Results
There were 681 689 total cancer deaths from 1997 to 2016, with 51.1% males and 48.9% females. Males had higher mortality rates than females. The ASMR ranged from 105.0 to 129.2 and 67.9 to 88.3 per 100 000 population per year among males and females, respectively. In 2004, the cancer mortality rate increased significantly among males (129.2 per 100 000 population), which was 1.5 times higher than in females (88.3 per 100 000 population). Among males, cancer of the lung had the highest YPPLL (394 779.3), followed by oesophageal (253 989.4) and liver (207 911.0). The YPPLL for cancer of the cervix (647 855.5) ranked first, followed by breast (483 863.6) and lung (146 304.6) in females.

Conclusion
Cancer mortality rates have increased since 1997, regardless of gender. Overall, there was a decline in YPPLL for cancer in the young population, while it increased in the adult population. A significant reduction in cancer deaths could be achieved by broadly applying effective interventions.

 

Study details

Advancing oncology drug therapies for sub-Saharan Africa

Kirthana Sharma, Tina Mayer, Sharon Li, Sadaf Qureshi, Faheem Farooq, Peter Vuylsteke, Tlotlo Ralefala, Richard Marlink.

Published in PLOS Global Public Health on 27 June 2023

Abstract

Cancer incidence is rising across sub-Saharan Africa (SSA), and is often characterised by late-stage presentation, early age of onset and poor survival. While a number of oncology drugs are now improving the length and quality of life for cancer patients in high-income countries, significant disparities in access to a range of oncology therapeutics exist for SSA. A number of challenges to drug access such as drug costs, lack of infrastructure and trained personnel must be urgently addressed to advance oncology therapies for SSA. We present a review of selected oncology drug therapies that are likely to benefit cancer patients with a focus on common malignancies in SSA. We collate available data from seminal clinical trials in high-income countries to highlight the potential for these therapeutics to improve cancer outcomes. In addition, we discuss the need to ensure access to drugs within the WHO Model List of Essential Medicines and highlight therapeutics that require consideration. Available and active oncology clinical trials in the region is tabulated, demonstrating the significant gaps in access to oncology drug trials across much of the region. We issue an urgent call to action to address drug access due to the predicted rise in cancer burden in the region in coming years.

South African Medical Journal Cancer mortality trends in South Africa: 1997 – 2016

PLOS article – Advancing oncology drug therapies for sub-Saharan Africa (Open access)

Health Policy Watch article – Africa’s High Cancer Deaths Can Be Addressed by Improved Access to Key Medicines (Open access)

 

See more from MedicalBrief archives:

 

Cancer deaths doubling, could soar to 1m in sub-Saharan Africa by 2030

 

Ageing population contributes to high cancer deaths in SA

 

Device to ID Kaposi sarcoma escalates treatment for sub-Saharan patients

 

For cancer patients with HIV, immunotherapy appears safe

 

 

 

 

 

 

 

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