Medires Publishers - Article

Abstract

Background: Prostate cancer has constituted a big public health challenge, evidenced and characterised by increasingly high incidence and prevalence rates.

Objective: This study narratively reviewed the incidence, prevalence, burden, issues and prospects of prostrate cancer in Nigeria to generate evidence for policy and planning.

Methods: The research was a narrative review of all studies conducted on the incidence, prevalence, burden, issues, and prospect of prostrate cancer in Nigeria from 1970 to 2023.

Overall, total of 139 articles were obtained, 79 from Pubmed, 35 from ResearchGate and 10 from Google Scholar. After a thorough evaluation, 55 duplicate articles were screened out, and 50 articles were also excluded for not covering the scope of incidence, prevalence, burden, issues, and prospect of prostate cancer in Nigeria. A total of 33 articles were used for the study. Data were summarized and presented in evidence-based tables.

Results: The studies obtained were predominantly retrospective and cross-sectional studies. Most of the studies were carried out between 2010 to 2023. Prostate cancer screening uptake was hampered by socioeconomic constraints and poor risk perception. Early detection might be enhanced by population-based PSA screening, however economics must be considered.

Conclusion: The increase in the rates of incidence and prevalence of prostate cancer from 1970 to 2023 makes it necessary to call for strategic health policymakers for immediate interventions to stop the trends. These trends are largely affected by lifestyle factors, age, and poor information in the awareness of the disease.

Introduction

Prostate cancer is among the most, if not the most common, cancers in men in the country, with a high morbidity and mortality. From systematic review studies, the incidence of this disease is more than 127 cases per 100,000 men annually and is expected to rise as a result of increasing life expectancy and urbanization. For decades now, prostate cancer has constituted a big public health challenge, evidenced and characterised by increasingly high incidence and prevalence rates [1-3]. These projections have become very necessary to understanding the basic factors that lead to the burden and issues, including cultural, socio-economic, and healthcare-related concerns. Several studies have shown that the prevalence of prostate cancer is the most common among men, accounting for more than 18.2% of all diagnosed cancers in men [4]. Corroborating this, the Nigerian National Cancer Registry has reported the high prevalence and high mortality, with an estimation yearly death rate of about 20,000 [1,5]. This high figure invariably implies the need for early screening, detection, and proper diagnosis to manage this disease.

In spite of the high prevalence and burden of prostrate cancer, awareness and knowledge of this disease are significantly low in Nigeria. This shows that a lot of people, particularly men, are not aware of this disease, these screening methods, and this diagnosis. Only 5% of the findings are confirmed in specific regions of the country [6,7]. This low awareness has some cultural belief systems in various communities and hinders victims from seeking medical attention early enough until the disease has come to an advanced stage [6,8]. At this stage, symptoms deteriorate and complications set in, leading to low survival rates [1,9].

The poor healthcare system in Nigeria has invariably contributed to the high burden of prostrate cancer. These include resource constraints, infrastructural limitations, inadequately trained healthcare personnel and poor diagnostic and screening tools that lead to poor management and follow-up [1,10]. Good awareness through screening programs for early detection and diagnosis is lacking in the country [5,11] This deficiency of awareness, detection, and late diagnosis has led to severe symptoms, weak prognosis, and treatment failures. Although cancer care has been integrated into primary healthcare, accessibility to early interventions and screening has been inadequate [2,5].

The socioeconomic implications of the disease in Nigeria are deeply felt, as communities and families are badly affected by this public health challenge. The financial implications and burdens are consequently overwhelming where the low-income groups and the under-served are deeply affected [5,12]. More so, the loss of productivity and the cost of illness and premature deaths have led to decreased economic output at both the household and national levels [13-16]. The cost of cancer management has been found to increase with population growth; hence, there is a need to address these needs very urgently and avert possible mortalities.

A recent study has shown that a community in Anambra State in the south-eastern part of Nigeria had demonstrated a strong desire to pay for a screening test PSA (Prostrate Specific Anlagen) and undergo a screening exercise for the early detection and treatment, which can invariably enhance both economic and health outcomes [1]. Properly planned collaborative efforts involving international organisations, non-governmental organisations, and the government can proffer solutions to these inherent challenges of prostate cancer in Nigeria[17-20]. This can be done through partnering in the areas of funding, creating awareness and strategies for good screening exercises and treatment guidelines, thereby reducing the socio-economic burdens very considerably.

Research Question

1. What is the pattern and demographics in the incidence and prevalence of prostrate cancer in Nigeria from 1970 to 2023?
2. What are the basic burden parameters inherent with prostrate cancer in Nigeria vis-à-vis socio-economic, cultural, and health care-related influences?
3. What are the possible barriers and challenges facing prostrate cancer patients as they concern timely detection, screening, and diagnosis with effective treatment in Nigeria?
4. What prospects exist for enhancing and creating prostate cancer awareness in Nigeria?

Methods

Study area: This narrative review covered published studies carried out in Nigeria from 1970 to 2023 on incidence, prevalence, burden, issues, and prospect of prostrate cancer. 

Literature Search Strategy

Databases: A comprehensive review was conducted using multiple databases to cover a broad collection of literature from PubMed, ResearchGate and Google Scholar.

Study design: The research was a narrative review of all studies conducted on the incidence, prevalence, burden, issues, and prospect of prostrate cancer in Nigeria from 1970 to 2023.

Study Criteria

Inclusion Criteria

1. Studies carried from 1970 to 2023
2. Peer-reviewed articles, government reports, and policy papers
3. Literature that focused on Nigeria only
4. Studies that addressed the incidence, prevalence, burden, issues, and prospects of prostate cancer

Exclusion Criteria

1. Articles not written in English
2. Studies not within the defined timeframe
3. Studies without complete data and flaws in methods were eliminated.

Article Search Process

Search Terms:

"Prostate Cancer" AND Incidence

Prostrate cancer AND prevalence

"Prostatic Carcinoma" AND Burden

"Prostate Cancer" AND Risk Factors

Boolean Operators: Boolean operators were utilised (AND, OR, NOT) as a proper combination of keywords. For instance, prostate cancer” AND “Nigeria”

Abstracts of relevant publications were screened. A computerised systematic search of all research works on prostate cancer published in PubMed, ResearchGate and Google Scholar was carried out. A manual search was also conducted for studies that met the inclusion criteria. The search was carried out independently, and only studies that met the criteria for the review were selected. 

Screening and Selection Process: Full-text versions of selected articles were obtained and their relevance based on the inclusion criteria assessed. Also extracted were the key information relevant to the review themes.

Data Extraction: Develop a data extraction format created to systematically capture all the relevant information from each study, which included the following:

Citation: Author(s), year of publication, title, and journal

Study Design: Type of study (e.g., observational, cross-sectional, qualitative)

Setting: Geographical location within Nigeria

Incidence and prevalence rates: statistical data reported

Burden: Impacts on public health, economy, and regulation

Key issues were highlighted: Challenges and barriers in curbing prostate cancer

Prospects: recommendations proffered with solutions suggested by the authors

Article Selection Process

A total of 139 articles were obtained, 79 from Pubmed, 35 from ResearchGate and 10 from Google Scholar. After a thorough evaluation, 55 duplicate articles were screened out, and 50 articles were also excluded for not covering the scope of incidence, prevalence, burden, issues, and prospect of prostate cancer in Nigeria. More screening exercise was carried out for the exclusion of 1 article due to incomplete study design and follow-up data, leaving 33 studies for use in the review.

Synthesis of Findings

Thematic Analysis: The extracted data were organised into thematic categories based on the issues identified. (incidence, prevalence, burden, issues, and prospects). This was to facilitate a structured narrative synthesis. All the quantitative data were integrated (e.g., prevalence rates, incidence statistics) with relevant findings (e.g., expert opinions, case studies) for a comprehensive insight into the topic. Findings across different studies were compared to highlight trends, variations, and insights regarding the prostate cancer overview in Nigeria.

Data Presentation

Data were presented in evidence-based format tables.

Ethical Approval

Ethical approval not needed in reviews. However, only researches with ethical approvals were included in the review.

Flow Chart

Fig 1: Study Articles selection process flow chat.

Results

Table 1: Summary of studies on the incidence and prevalence of prostate cancer in Nigeria

Table 2: Burden and Risk Factors for Prostate Cancer in Nigeria

Table 3: Barriers to Prostate Cancer Screening and Diagnosis in Nigeria

Table 4: Prospects for Improving Prostate Cancer Outcomes in Nigeria

Discussion

Several studies have examined very deeply the incidence, burden, and prevalence of prostrate cancer in Nigeria. Umeh et al. investigated the desire and willingness to pay for the screening exercise of PSA tests in Anambra State, Southeastern Nigeria. The studies showed that some parts of the study population were willing to pay for the PSA screening exercise even though costs posed challenges and barriers for the underserved groups. The study revealed that early PSA screening exercise improved early detection; however, the cost component needed to be addressed for affordability purposes [1]. A retrospective study carried out in Benin City, Nigeria, showed that prostrate tumours accounted for a great percentage of cancers in the male population, which showed an increasing pattern over the years [3].

This is an indication of the increasing incidence of prostrate cancer, implying immediate intervention by healthcare professionals to reverse the trend. An autopsy report by another investigation highlighted much higher prevalence rates of prostrate cancer than reported by previous studies, suggesting cases that were poorly diagnosed or not diagnosed at all. The studies recommended more screening exercises to address the issue [14].

Systematic review studies carried out in several hospitals and clinics had shown increasing incidence rates of prostrate cancers across and within Nigeria, especially in urban areas, implying that lifestyle changes and urbanisation played major roles in prostrate cancer. [16] However, some studies reviewed and discovered variabilities in incidence across several regions of Nigeria, showing gaps in national data collection, indicating the need for improved data systems in national cancer registries [9]. In another systematic and meta-analysis review carried out by a study, an increase in prostrate cancer incidence in Africa as a whole portrayed Nigeria as having the highest rates. This calls for the need to enhance cancer surveillance and screening programs to lessen the burden [20]. Again, the study conducted by Oluwole et al. discovered an upward rise in prostrate cancer incidence in ABUTH Zaria in a ten-year period, suggesting better screening and diagnostic methods [16,21]. Studies also carried out in 2012 from population-based cancer registries showed that prostate cancer was the most prevalent form of cancer among men, with geographic variations in incidence suggesting the need for establishing, running, and maintaining population-based registries[28]. The report compared favourably with the burden of prostrate cancer among the black race worldwide, West Africa included, indicating that genetic and environmental factors adequately contributed to the high incidence, thereby calling for more collaborative studies to address disparities [29].

Burdens and risk factors for prostrate cancer have been conducted comprehensively by several researchers. Investigations carried out in Calabar, Nigeria, showed higher mortality rates in the more elderly men with advanced-stage diagnosis, implying the need for early diagnosis for better survival rates [5]. Similarly, a retrospective cohort study revealed that prostate cancer patients often presented with comorbidities, e.g., hypertension and diabetes, making treatment outcomes more complicated, hence emphasising the importance for elaborate and comprehensive management [7]. Ogunbiyi listed major barriers such as infrastructural limitations and a lack of trained professionals as hindering factors towards cancer control in Nigeria [2,15]. Adesina et al. had identified several gaps in knowledge and preventive measures on prostrate cancer in Kwara State, urging for educational interventions[23].

A cross-sectional study in rural areas in Nigeria carried out by Ukoli et al. discovered that about 19% of men had elevated PSA levels suggestive of a higher risk of prostrate cancer without awareness and accessibility to screening tests being of major concern.[22] In a previous study carried out by Adesina et al., they showed concern about the increasing burden of communicable diseases, including prostrate cancer, and urged for comprehensive national policies that direct interest on prevention and detection of early prostrate cancer [23]. Baba et al. had earlier investigated the incidence and risk factors in Nigeria, associating the rise in risk factors to ageing, genetics, and lifestyle influences, suggesting regional collaborative studies in prostate cancer [25]. Ugwumba et al. discovered that most prostrate cancer patients in the black African region presented with end-stage disease, recommending the necessity for early diagnosis [9,33]. Oladimeji et al. had equally examined awareness and screening exercises in Oyo State and discovered that decreased awareness levels and screening practices, calling for urgent public health campaigns to increase screening practices[30].

Ndikom and Ilesanmi had examined barrier factors and discovered that poor risk perception coupled with some socioeconomic barriers had impacted negatively on the screening practices in Ibadan, implying a suggestion to enhance screening uptake [19]. Umeh et al. had discovered that affordability played a measurable role in screening, with many patients willing to pay minimally for PSA tests, which called for government subsidies for health programs [1]. On the other hand, Ariom et al. found that a low knowledge base and fear of the diagnosis being positive were strong barriers to screening participation among male artisans in Nnewi-North, suggesting education and community outreaches [11]. Enemugwem et al., in their studies, discovered that cultural stigma was a big barrier to screening exercises in Obio Akpor, with most of the patients unwilling to partake—a call to address cultural beliefs in their awareness campaigns [27]. Omisanjor et al.'s research highlighted long waiting times for diagnosis and called for better diagnostic capacity for earlier detection [28].

Misconceptions about prostrate cancer in Nigeria were investigated by Osegbe, and he found poor awareness and misconceptions were prominent factors that played down on detection rates [17]. Awosan et al. found out that only 22.4% of men were aware of prostrate cancer in Sokoto State, identifying weak knowledge base and calling for education campaign improvements [24]. A review study carried out by Busola and Woodgate on prevention strategies highlighted limited infrastructure and poor awareness as major barrier factors to prostate cancer screening exercise across African countries and proffered stronger health systems and community programs [26] in his survey, highlighted cultural stigmas, limited healthcare access, and financial constraints as strong barriers to early diagnosis in remote parts of Nigeria, advising for a well-tailored intervention[22]. Abdusalam, et al had proposed in his works that brachytherapy may be a better treatment approach for prostate cancer while Chiedebe et al., suggested that early detection and treatment be adopted by National cancer control program to reduce the burden of prostate cancer [31]. Akinwemi et al had investigated the gaps in recent research works and found out that strengthening National policy reforms, promoting early detection and education can lessen the incidence and prevalence of prostate cancer.

Conclusion

The increase in the rates of incidence and prevalence of prostate cancer from 1970 to 2023 makes it necessary to call for strategic health policymakers for immediate interventions to stop the trends. These trends are largely affected by lifestyle factors, age, and poor information in the awareness of the disease. The barriers to be removed include delays in detection and treatment of the disease, limited access, and cultural stigma, which worsen the diseases. To lessen the impacts of prostate cancer, stakeholders approach is advocated to improve public health care education by creating awareness programs to increase early detection and treatment of prostate cancer through early screening exercise. There is also a need to strengthen the national cancer control program and initiate the teamwork approaches of health care professionals, policymakers, and NGOs to create a conducive working environment for prostate cancer care and management.

Limitations

Firstly, the work relied mostly on secondary data collection, which may not be consistent with the adopted varying reporting patterns, different methods of research designs, and study setting disparities in prostate cancer awareness and diagnosis. Considering the long span of coverage and limited information on longitudinal data, the study may not have captured the various variations in data on incidence and prevalence. Limiting the study to Nigeria alone may not represent global information on incidence, prevalence, and burden of prostate cancer.

Conflict of interest: The authors have none to declare.

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