A systematic review and meta-analysis of the prevalence and risk factors of prostate cancer in Nigeria

Abstract

Background

Prostate cancer (PCa) remains a leading cause of morbidity and mortality among men worldwide, with significant regional variations in prevalence and risk factors. In Nigeria, data on prostate cancer prevalence remain inconsistent due to limited screening and reporting systems.

Aim

This systematic review and meta-analysis aimed to synthesise available evidence on the prevalence and associated risk factors of prostate cancer among Nigerian men.

Methods

A systematic search of PubMed, Scopus, Embase, Medline, and CINAHL was conducted using preferred reporting items for systematic reviews and meta-analysis [PRISMA] guidelines. Six high-quality observational studies involving a total sample size of 9,659 men were included. Data were extracted and analysed using a random-effects meta-analysis model using Review Manager software 5.4.1. Risk of bias was assessed using the CASP checklist for observational studies.

Results

The pooled prevalence of prostate cancer in Nigeria was low but highly heterogeneous across studies (OR = 1.07, 95% CI [1.03, 1.12], p = 0.0006; I² = 100%). Community-based screenings and autopsy studies reported lower prevalence rates compared to hospital-based studies. Age and genetic predisposition were consistent primary risk factors, with lifestyle factors, family history, and delayed healthcare access contributing to advanced disease stages.

Conclusion

This meta-analysis found a low but variable prevalence of prostate cancer in Nigeria, driven by differences in screening access and late-stage diagnosis. Age and genetic predisposition were consistent risk factors, alongside modifiable factors such as lifestyle and delayed healthcare seeking. The findings emphasise the need for improved national screening, strengthened cancer registries, genetic counselling, and public health education to reduce the burden of prostate cancer among Nigerian men.

Introduction

Prostate cancer continues to pose a major global public health challenge, with its burden differing widely across regions due to variations in genetics, environmental exposures, and socioeconomic conditions [1, 2]. Globally, it ranks as the second most frequently diagnosed malignancy among men, accounting for an estimated 1.4 million new cases and about 375,000 deaths in 2020 [3]. However, this global figure conceals substantial regional disparities in both incidence and mortality. In high-income regions such as North America and Western Europe, the prevalence of prostate cancer is considerably higher, largely attributable to the widespread use of prostate-specific antigen (PSA) screening that facilitates early detection [4]. Conversely, in many low- and middle-income countries, including those in sub-Saharan Africa and parts of Asia, the reported prevalence remains low, primarily because of limited access to screening and diagnostic services [5]. Mortality rates are, however, significantly higher in African and Caribbean populations, where late presentation and inadequate treatment infrastructure remain critical barriers to improved outcomes [6]. This imbalance is further compounded by weak cancer registries and underdeveloped health systems across much of Africa, which hinder accurate disease surveillance and reporting [7]. Collectively, these disparities underscore the urgent need for comprehensive epidemiological investigations to better understand and address the true burden of prostate cancer globally.

Genetic susceptibility remains one of the strongest determinants of prostate cancer risk. Vietri et al. [8] emphasize that hereditary factors play a major role in disease development, with men who have first-degree relatives diagnosed at an early age being particularly vulnerable. Saunders et al. [9] further identify several germline mutations—including BRCA1, BRCA2, HOXB13, and ATM—as key genetic alterations that heighten prostate cancer risk, noting that BRCA2 mutations are often linked to more aggressive forms of the disease. In a similar context, Khan and Cheng [10] highlight that men of African ancestry possess specific inherited polymorphisms and allele variations that increase their likelihood of developing aggressive prostate cancer phenotypes. Building on this, Seibert et al. [11] propose that genetic risk prediction models could enhance targeted screening and early detection, particularly among populations with high hereditary susceptibility.

Beyond genetic predisposition, several modifiable risk factors have been identified. Evidence indicates that obesity, poor dietary habits, and physical inactivity significantly contribute to prostate cancer progression [1]. Rivera-Izquierdo et al. [12] strengthen this association by demonstrating a link between obesity, metabolic syndrome, and increased mortality, suggesting that disrupted metabolic pathways may promote tumour growth. In addition, Coughlin [13] and Zhu et al. [14] reveal the role of social determinants such as socioeconomic status, access to healthcare, and racial inequality in shaping both the incidence and survival outcomes of prostate cancer. More recently, Fujita et al. [15] introduced the concept of the gut–prostate axis, proposing that alterations in gut microbiota composition may influence prostate carcinogenesis through immune and hormonal pathways. Similarly, Mukherjee and Gopalakrishnan [16] point to environmental exposures—particularly endocrine-disrupting chemicals as potential contributors to hormonal imbalances that facilitate prostate tumour development. Despite these advances, Bosland et al. [17] observe that the exact interactions between lifestyle, environmental, and genetic factors remain poorly understood, warranting further mechanistic research to clarify their combined influence on prostate cancer pathogenesis.

Despite numerous studies examining prostate cancer prevalence and associated risk factors, significant knowledge gaps persist particularly regarding country-specific patterns in low- and middle-income settings. The global evidence base remains fragmented, and variations in study designs, diagnostic criteria, and population demographics have limited cross-study comparability [18]. James et al. [18] note that inconsistencies in diagnostic approaches, population selection, and data reporting have hindered accurate trend estimation, while Berenguer et al. [19] emphasize that existing meta-analyses on genetic and lifestyle determinants rarely account for regional disparities or incorporate emerging biomarkers in their risk models. Consequently, there is a lack of synthesised evidence that integrates the epidemiological, clinical, and contextual realities of prostate cancer in specific African nations.

Nigeria, in particular, represents a critical context for investigation due to its high disease burden and distinct epidemiological characteristics within the African region. Previous studies have shown that Nigerian men often present with more aggressive and advanced disease stages compared to their Western counterparts, a pattern largely attributed to genetic predisposition, late detection, and poor access to routine screening services [16, 20]. Moreover, systemic challenges such as weak cancer registry systems, inadequate healthcare infrastructure, low public awareness, and socioeconomic disparities continue to contribute to underdiagnosis and delayed management of prostate cancer in the country [21, 22].

To address these gaps, this systematic review and meta-analysis consolidates existing Nigerian studies to generate a pooled estimate of prostate cancer prevalence and to identify the most consistent risk factors. By contextualizing evidence within Nigeria’s healthcare and sociocultural environment, this study aims to provide a more accurate epidemiological framework that can guide national screening policies, public health strategies, and future research priorities.

Methods

The protocol for this systematic review and meta-analysis has been registered in the International Prospective Register of Systematic Reviews database was registered as https://www.crd.york.ac.uk/PROSPERO/view/CRD420251229893. This systematic review and meta-analysis used the preferred reporting items for systematic reviews and meta-analysis known for short as the (PRISMA) [23].

Search strategy and selection criteria

Informatively, a systematic search strategy is a structured and comprehensive approach to identifying relevant literature for a systematic review, ensuring that all pertinent studies are included while minimizing bias [24, 25]. However, this review incorporated the use of major biomedical databases, including PubMed, Scopus, Embase, Medline, and CINAHL, to retrieve relevant studies, ensuring that the search process was enhanced using Medical Subject Headings (MeSH) terms in combination with primary keywords to improve the specificity and sensitivity of the search. However, the primary keywords used in this search included “Prostate Cancer,” “Prevalence,” “Risk Factors,” “Genetic Susceptibility,” “Lifestyle Factors,” and “Environmental Exposure”. Boolean operators such as AND, OR, and NOT were applied to refine the search results. Then, the AND operator was used to combine different concepts, ensuring that retrieved articles contained all specified terms (e.g., “Prostate Cancer AND Risk Factors”). The OR operator broadened the search by including synonyms (e.g., “Genetic Susceptibility OR Hereditary Risk”). The NOT operator excluded irrelevant studies by filtering out terms that weren’t needed. Additionally, truncation (e.g., “cancer*”) allowed for capturing multiple word variants, while wildcards (e.g., “wom? n” for “woman” and “women”) facilitated inclusive searches. Proximity searching was also employed to retrieve records where key terms appeared within a defined word distance, enhancing retrieval precision and to further enrich the dataset, the reference lists of potential articles were screened manually for additional relevant studies. Meanwhile, the search strategy is represented in appendix one.

The PEO (Population, Exposure, Outcome) framework, was used to structure the inclusion and exclusion criteria [26, 27]. The population (P) comprised of studies on men diagnosed with prostate cancer across Nigeria. The exposure (E) consisted of different genetic, lifestyle, and environmental risk factors related to prostate cancer. The outcome (O) concentrated on the prevalence and associated risk factors of prostate cancer. Meanwhile, studies that did not involve prostate cancer patients and studies not involving prostate cancer patients in Nigeria. Systematic reviews, commentaries, opinions, letters to editors, grey literature, dissertations, non-peer reviewed articles were excluded. The search was conducted from 2010 till 2025 Appendix two gives a more detailed information of the eligibility criteria of this review.

The study selection being a critical step in systematic review, involves the process of identifying, screening, and including relevant studies based on predefined eligibility criteria [28, 29]. However, to ensure accurate and efficient selection process, EndNote reference management software was used to enhance the de-duplication of articles that has been retrieved from different databases and the search was carried out following the predefined search strategy and ensuring that there was an inclusion of all relevant literature. Meanwhile, the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) diagram was utilized to systematically document the study selection process, recording the number of studies that were identified, screened, assessed for eligibility, and was finally dimmed fit for inclusion in the review [30].

Quality assessment

The research quality was assessed using the Critical Appraisal Skills Programme (CASP), and it as a widely recognized tool designed to determine the validity, credibility, and applicability of research papers [31]. key methodological considerations included study design, sample size, data collection techniques, statistical analysis, and the validity of conclusions and studies based on the results generalizability, potential biases, and confounding elements were rigorously assessed. However, high-quality studies with strong methodological frameworks, well-defined research goals, and solid data analysis were prioritized for inclusion and using a rating system adapted from the CASP checklist which classified studies as high, moderate, or low quality, with high-quality studies demonstrating rigorous methodologies, appropriate statistical analyses, and minimal bias, while low-quality studies had methodological flaws that couldn’t be ignored. Two reviewers independently ascertained the risk of bias of the study and disagreements were resolved by consensus or consultation with a third reviewer.

Data extraction

For the data extraction Microsoft Excel was used to perform the data extraction of the included studies, ensuring a well-structured and efficient process. Two reviewers independently screened and extracted data, and disagreements were resolved by consensus or consultation with a third reviewer. Meanwhile, a standardized data extraction form was employed to capture important information, which includes study title, author(s), year of publication, country of study, study design, sample size, population characteristics, exposure factors (genetic, lifestyle, environmental), reported outcomes (prevalence and risk factors), and key findings.

Data synthesis

Data synthesis in systematic reviews involves putting together findings from multiple studies to derive meaningful conclusions and there are two primary methods of data synthesis which are narrative synthesis and meta-analysis [32]. Narrative synthesis is however a qualitative approach that involves summary and explanation of patterns across studies, which makes it useful for heterogeneous data, although, due to subjectivity and potential bias there is a limitation [33]. In contrast, meta-analysis is a quantitative method that centres on the combination of data from multiple studies statistically, providing more results that are objective and generalizable and despite its advantages, meta-analysis is limited by study design heterogeneity, sample populations, and measurement outcomes, which can affect the validity of pooled estimates [31, 34].

The methods of meta-analysis include fixed-effect and random-effects models, on which the fixed-effect models assume that all studies estimate the same underlying effect, making them suitable for homogenous data, while random-effects models account for between-study variability and providing more generalized estimates [34]. However, the random-effects model is prone to increased variance and wider confidence intervals, which can reduce precision [31]. For this review, a random effect meta-analysis approach using the RevMan software version 5.4.1 was adopted to estimate the prevalence and a narrative synthesis was used to discuss the associated risk factors across different studies, enhancing the reliability of conclusions.

Results

Overview of the search process

A total of 855 studies were identified across the databases that were included in this review and following the entire de-duplication and screening process, it resulted to the inclusion of six (6) studies for this review [17, 35–39]. The PRISMA flow diagram in Fig. 1 below shows in details the stages and reasons for exclusion of articles.

Fig. 1.

PRISMA flow diagram (adopted from Page et al., 2021)

Characteristics of the included studies

A total of 10,494 participants were involved across the six studies included in this analysis [17, 35–39]. Table 1 below illustrates the detailed characteristics of the studies.

Table 1.

Characteristics of the included studies

Study Author	Study Title	Study Design	Sample Size & Population Characteristics	Exposure Factors	Reported Outcomes	Setting
Ikuerowo et al. (2013)	Prevalence and characteristics of prostate cancer among participants of a community-based screening in Nigeria using serum prostate specific antigen and digital rectal examination	Community-based cross-sectional study	4172 men screened; 4110 with complete data; age > 40 years; mean age 60.8 years	Age, lifestyle	Prevalence: 1.046% (1046 per 100,000); 74% had Gleason score ≥ 7; 40% locally advanced, 35% metastatic	Lagos State
Bosland et al. (2021)	Prevalence of prostate cancer at autopsy in Nigeria—A preliminary report	Autopsy-based observational study	39 prostates from deceased men aged > 40 years; mean age 55 ± 11 years	Genetic, environmental	Prevalence: 8.8% subclinical prostate cancer; 20.6% had high-grade prostatic intraepithelial neoplasia (HGPIN)	Lagos & Calabar States
Ezenwa et al. (2012)	Prevalence of prostate cancer among Nigerians with intermediate total PSA levels (4–10 ng/mL): Experience at Lagos University Teaching Hospital, Nigeria	Hospital-based cross-sectional study	105 men aged ≥ 50 years; mean age 64.4 years; PSA 4–10 ng/mL; normal DRE findings	Age, lifestyle	Prevalence: 13.3%; all adenocarcinoma; Gleason score 5–7 predominated	Lagos State
Ngwogu et al. (2019)	Prevalence and histopathological patterns of prostate cancer in Abia State University Teaching Hospital, Aba, South Eastern Nigeria	Retrospective histopathological review	135 prostate cancer cases from 2007–2016; age range 42–90 years; mean 72 ± 10.2 years	Age, late presentation	Prevalence: 10.4% of male malignancies; Gleason scores 6–9; majority moderately or poorly differentiated adenocarcinomas	Abia State
Esomonu et al. (2024)	Prevalence of benign prostatic hyperplasia and prostate cancer among suburban residents in Southern Nigeria	Cross-sectional community study	1179 men aged ≥ 44 years; suburban towns	Family history, lifestyle, diet	PCa prevalence: 0.81%; BPH prevalence: 16.67%; higher rates in men aged 60–80 years	Cross River State
Ntekim et al. (2023)	The prevalence of prostate cancer among young men below 55 years of age in Nigeria	Cancer registry retrospective study	Data from 4864 malignancy cases in men < 55 years; 4091 PCa cases total	Genetic, lifestyle	8.86% of PCa cases in men < 55 years; regional prevalence: North 11.72%, South 7.77%	National data from 15 Nigerian cancer registries

Quality assessment results

The risk of bias assessment was conducted using the Critical Appraisal Skills Programme (CASP) tool for quantitative observational studies across ten domains. Each study was scored 1 point per domain met, yielding a maximum score of 10. Domains assessed included research clarity, methodology, population definition, sample size, exposure and outcome measurements, confounder consideration, results presentation, statistical analysis, and ethical approval. All six studies scored between 8 and 10, indicating high methodological quality. Most studies lacked detailed sample size justification and explicit confounder adjustment. Full scoring and study-specific ratings are presented in Appendix 3 (Table of CASP quality ratings).

Results

Meta-analysis of the pooled prevalence of prostate cancer in Nigeria

As shown in Fig. 2 the meta-analysis pooled data from six high-quality studies reporting prostate cancer prevalence among Nigerian men. A random-effects model was used due to expected heterogeneity across studies in population size, setting, and diagnostic methods. The overall pooled prevalence of prostate cancer in Nigeria was low but showed notable variability between studies OR = 1.07(95% CI[1.03, 1.12], p = 0.0006). Studies based on autopsy and community screening reported lower prevalence, while hospital-based studies reported higher rates, likely reflecting referral bias and late presentation. The pooled estimate provides a more representative measure of the burden of prostate cancer in Nigeria compared to individual studies. Significant heterogeneity was detected (I² =100%, p < 0.00001), indicating variability between study results. This reveals the urgent need for standardized national screening programs and early detection strategies to address the burden of prostate cancer in Nigeria.

Fig. 2.

Forest plot demonstrating the pooled prevalence across the studies on prostate cancer in Nigeria

Risk factors of prostate cancer in Nigeria

The six studies as shown in Table 2 included in this meta-analysis collectively highlighted key risk factors associated with prostate cancer (PCa) among Nigerian men, with consistent emphasis on age, genetic predisposition, lifestyle, and environmental factors. Age emerged as a primary risk factor, with the mean ages of diagnosed patients ranging from 55 to 72 years across studies, reflecting the established correlation between increasing age and PCa incidence [17, 35–39]. Several studies also suggested that genetic and familial predisposition may contribute to the disease burden, as evidenced in Bosland et al. [17], who reported the presence of subclinical PCa at autopsy, and Ntekim et al. [39], who documented a notable proportion of young-onset PCa cases below 55 years, indicating potential inherited susceptibility. Lifestyle and environmental factors, including diet and healthcare access, were explored with varying degrees of depth; Esomonu et al. [38] particularly noted the influence of family history, lifestyle habits, and dietary patterns on disease occurrence. Ngwogu et al. [37] further reported late presentation and poor health-seeking behaviours as contributors to advanced-stage diagnoses, a factor also emphasized by Ikuerowo et al. [35], who found that 74% of their patients presented with high Gleason scores of ≥ 7, indicating aggressive disease forms. Similarly, Ezenwa et al. [36] highlighted a high prevalence of adenocarcinoma in Nigerian males with intermediate PSA levels, stressing the relevance of biochemical markers in early risk identification. These findings reinforce that PCa in Nigeria is driven by a complex interplay of non-modifiable (age, genetics) and modifiable (lifestyle, delayed healthcare access) risk factors, requiring multifaceted intervention strategies [17, 35–39].

Table 2.

Summary of associated risk factors of prostate cancer in the included studies

Study	Age-Related Risk	Genetic/Familial Risk	Lifestyle/Environmental Risk	Delayed Diagnosis/Healthcare Access	Notes
Ikuerowo et al. (2013)	Strong correlation; mean age 60.8 years; older men more affected	Not directly assessed	N/A	High prevalence of late-stage disease; 74% had Gleason score ≥ 7	Community-based screening
Bosland et al. (2021)	Mean age 55 years	Subclinical PCa at autopsy suggests inherited susceptibility	N/A	N/A	Autopsy study; detected asymptomatic disease
Ezenwa et al. (2012)	Mean age 64.4 years; age positively linked to PCa detection	N/A	N/A	Detected PCa in men with intermediate PSA, supporting role of early biochemical testing	Hospital-based diagnostic study
Ngwogu et al. (2019)	Mean age 72 years; peak diagnosis in 7th decade	N/A	N/A	Late presentation; patients presented with poorly differentiated adenocarcinoma	Retrospective histopathological study
Esomonu et al. (2024)	Significant age gradient; highest rates in men 60–80 years	Family history noted as a key factor	Lifestyle factors and dietary patterns reported	N/A	Community-based cross-sectional study
Ntekim et al. (2023)	Younger onset PCa (< 55 years); proportion 8.86%	Early disease in young men suggests genetic/familial susceptibility	N/A	N/A	Registry study; focus on young-onset prostate cancer

^*N/A = Not accessed

Discussion

The main objective of this review was to determine the prevalence and risk factors of prostate cancer in Nigeria. The findings of this meta-analysis revealed a low overall pooled prevalence of prostate cancer (PCa) in Nigeria, despite significant heterogeneity across studies. This observation aligns with previous epidemiological studies, which consistently report that African nations, including Nigeria, tend to have lower recorded incidences of prostate cancer compared to Western countries, primarily due to underdiagnosis, poor cancer registry systems, and limited access to screening [3, 7]. However, it is important to note that the true burden may be significantly underestimated, as hospital-based studies like those included in this review often reveal more advanced and aggressive disease patterns compared to community-based screenings, highlighting a systemic delay in diagnosis [4]. Comparatively, Bergengren et al. [1] reported that regions with structured PSA screening programs, like North America and parts of Europe, have much higher detection rates, suggesting that increased surveillance rather than true differences in incidence accounts for part of the disparity. Furthermore, the high heterogeneity observed in this review is consistent with prior meta-analyses, such as Jiang et al. [5], who noted considerable variation in prostate cancer prevalence between urban and rural populations within the same countries, attributed to socio-economic factors, healthcare accessibility, and educational disparities. This evidence collectively supports the argument that without widespread, accessible screening initiatives, Nigeria’s reported PCa prevalence remains an underestimation of the actual disease burden, reinforcing the need for national screening strategies and robust cancer registries. In addittion it is imperative to note that many of the included studies evaluated risk factors using self-reported or retrospective methods, which may introduce subjectivity.

Risk factors associated with prostate cancer identified in this meta-analysis notably age, genetic predisposition, lifestyle factors, and delayed healthcare access are congruent with wider scientific literature on prostate cancer aetiology. Age as a major risk factor was strongly corroborated across all six studies, with the mean age at diagnosis ranging from 55 to 72 years. This finding aligns with global reports by Gandaglia et al. [6] and Freedland et al. [2], who posit that prostate cancer risk escalates substantially with advancing age due to cumulative genetic mutations and hormonal changes, supporting the biological theory of “genomic instability” associated with ageing tissues [7]. Furthermore, the significant proportion of young-onset prostate cancer cases reported by Ntekim et al. [39] echoes prior findings by Saunders et al. [9] and Seibert et al. [11], which highlighted the role of hereditary genetic mutations, particularly BRCA2, HOXB13, and ATM, in predisposing younger men to more aggressive disease phenotypes. In Nigeria, where access to genetic testing remains limited, the actual contribution of hereditary factors may be underestimated, posing challenges for early intervention. Additionally, lifestyle and environmental factors highlighted by Esomonu et al. [38] — such as dietary habits and family history are consistent with the findings of Leitão et al. [40], who emphasized that diets high in saturated fats and low in fruits and vegetables, along with sedentary behaviour, are significant contributors to prostate cancer risk. Interestingly, these lifestyle factors can be interpreted through the ecological model of health behaviour, which suggests that individual health outcomes are influenced not just by personal choices but also by broader societal and environmental contexts [41], explaining regional differences in prostate cancer incidence even within Nigeria.

Moreover, the consistently reported late-stage presentation of prostate cancer among Nigerian men, as observed by Ikuerowo et al. [35] and Ngwogu et al. [37], resonates strongly with earlier observations by Coughlin [13] and Zhu et al. [14], who argue that socio-economic barriers, low awareness, cultural perceptions of cancer, and poor healthcare infrastructure significantly delay diagnosis and treatment. This trend is critically important because late-stage diagnoses are associated with higher Gleason scores and poorer prognoses, underscoring the aggressive nature of prostate cancer when detected late [2]. From a theoretical perspective, this pattern aligns with Andersen’s Behavioral Model of Health Services Use, which postulates that predisposing characteristics (such as socio-economic status), enabling resources (such as healthcare accessibility), and perceived need for services collectively influence healthcare utilisation [42]. The delayed health-seeking behaviours reported across the Nigerian studies mirror this theoretical framework, suggesting that interventions must not only focus on increasing screening availability but also address socio-cultural and economic barriers to healthcare access. In conclusion, this meta-analysis substantiates the prevailing view that prostate cancer in Nigeria is shaped by a complex interplay of biological, environmental, and systemic healthcare factors, necessitating comprehensive public health strategies that integrate early detection, health education, genetic counselling, and systemic reforms to reduce mortality and morbidity from this disease also future Nigerian research incorporate objective lifestyle measurements (e.g., validated dietary and physical-activity tools) and molecular genetic analyses to strengthen causal inferences.

Limitations

Some of the limitations of this systematic review and meta-analysis was the inclusion of small number of included studies, also publication bias and also heterogeneity in diagnostic methods identified during the review process. Also we now recommend that upcoming studies employ standardized diagnostic criteria, uniform PSA thresholds, and detailed reporting of sample characteristics such as age, region, and socioeconomic profile to improve comparability and reduce heterogeneity.

Implications of the findings

The findings of this meta-analysis carry significant implications for health policy, clinical practice, and public health interventions in Nigeria. The low pooled prevalence, coupled with high heterogeneity and evidence of late-stage presentation, highlights critical gaps in early detection and reporting systems, necessitating urgent policy reform towards the establishment of a national prostate cancer screening programme. Policymakers must prioritise funding for accessible and decentralised PSA screening and biopsy services, particularly in rural and underserved areas where underdiagnosis is most pronounced. Clinically, healthcare providers should incorporate risk stratification strategies, focusing on high-risk groups such as older men and those with family history or early-onset disease, as noted in Ntekim et al. [39] and Esomonu et al. [38]. Public health education campaigns are essential to improve awareness and combat cultural misconceptions and health-seeking delays, a factor strongly linked to poor outcomes in studies like Ikuerowo et al. [35] and Ngwogu et al. [37]. Additionally, the documentation of hereditary and lifestyle risk factors advocates for the integration of genetic counselling and lifestyle modification programmes into routine clinical practice [17, 36].

Conclusion

This systematic review and meta-analysis provides a comprehensive synthesis of the prevalence and risk factors of prostate cancer among Nigerian men. The pooled prevalence of prostate cancer in Nigeria was 1.07 (95% CI 1.03–1.12), equivalent to approximately 1,070 cases per 100,000 men. Findings confirm that prostate cancer in Nigeria is predominantly diagnosed at an advanced stage, largely due to delayed healthcare access, low screening rates, and inadequate public awareness. Age and genetic predisposition were consistently identified as primary non-modifiable risk factors, while lifestyle habits, family history, and poor health-seeking behaviours contributed as modifiable risks. The review highlights critical gaps in national screening policies and healthcare delivery systems, reinforcing the urgent need for targeted public health interventions, improved cancer registries, and nationwide early detection strategies. Addressing these gaps is essential to reduce prostate cancer morbidity and mortality in Nigeria.

Appendix

Appendix 1. Search strategy

S/N	Primary Keywords	MeSH Terms and Synonyms	Boolean Operators	Databases Searched
1	Prostate Cancer	"Prostatic Neoplasms" OR "Prostate Tumor" OR " Prostate Carcinoma" OR "Cancer of the Prostate" OR "Prostatic Carcinoma" OR "Prostatic Cancer" OR "Malignant Neoplasm of the Prostate" OR "Glandular Cancer" OR"Adenocarcinoma"	OR	PubMed, Scopus, Embase, Medline, CINAHL
2	Prevalence	"Epidemiology" OR "Incidence"	OR	PubMed, Scopus, Embase, Medline, CINAHL
3	Risk Factors	"Predisposing Factors" OR "Causal Factors"	OR	PubMed, Scopus, Embase, Medline, CINAHL
4	Genetic Susceptibility	"Hereditary Risk" OR "Genetic Predisposition" OR "Hereditary Predisposition" OR "Inherited Predisposition" OR "Genetic Vulnerability" OR "Inherited Susceptibility"	OR	PubMed, Scopus, Embase, Medline, CINAHL
5	Lifestyle Factors	"Dietary Habits" OR "Physical Activity" OR "Way of Life" OR "Everyday Routines" OR "Behavioral Patterns" OR "Living Habits" OR "Lifestyle Practices" OR "Mode of Living" OR "Life Choices"	OR	PubMed, Scopus, Embase, Medline, CINAHL
6	Environmental Exposure	"Carcinogens," "Endocrine Disruptors"	OR	PubMed, Scopus, Embase, Medline, CINAHL
		1 AND 2 AND 3 AND 4 AND 5 AND 6	AND	PubMed, Scopus, Embase, Medline, CINAHL

Appendix 2. Eligibility criteria

Items	Inclusion Criteria	Exclusion Criteria
Population	Men diagnosed with prostate cancer in Nigeria.	Studies not involving prostate cancer patients and studies not involving prostate cancer [atients in Nigeria.
Exposure	Genetic predisposition, lifestyle, and environmental risk factors.	Studies that do not assess risk factors for prostate cancer.
Outcome	Studies reporting prevalence and risk factors of prostate cancer.	Studies without clear outcomes related to prostate cancer prevalence and risk factors.
Study Design	Observational studies (cohort, case-control, cross-sectional), RCTs.	Systematic reviews, commentaries, opinions, letters to editors, grey literature, dissertations.
Publication Status	Peer-reviewed original studies	Preprints, unpublished reports, short communications
Study Duration	Studies published from 2010 to the present	Studies published before 2010
Language	English-language studies only	Non-English studies

Appendix 3: risk of bias assessment (CASP) table

Study (Author, Year)	Clear focus of the research	Appropriate methodology	Well-defined study population	Sample size justification	Accurate measurement of exposure	Accurate measurement of outcome	Consideration of confounding factors	Clear presentation of results	Appropriate statistical analysis	Ethical considerations / approval reported	Total /10	Quality
Ikuerowo et al. (2013)	1	1	1	1	1	1	0	1	1	1	9	High
Bosland et al. (2021)	1	1	1	0	1	1	1	1	1	1	9	High
Ezenwa et al. (2012)	1	1	1	0	1	1	0	1	1	1	8	High
Ngwogu et al. (2019)	1	1	1	0	1	1	0	1	1	1	8	High
Esomonu et al. (2024)	1	1	1	1	1	1	0	1	1	1	9	High
Ntekim et al. (2023)	1	1	1	0	1	1	0	1	1	1	8	High

Each study gets 1 point per criterion met, yielding a maximum of 10 points. I will then give an overall rating (High: 8–10, Medium: 5–7, Low: ≤4)

Authors’ contributions

Ikechukwu Nosike Simplicius Dozie (INSD): Conceptualization of the project idea, Protocol development, Project co-ordinationUchechukwu Madukaku Chukwuocha (UMC): Supervision, Methodology, Data synthesis.David Chinaecherem Innocent (DCI): Original draft preparation, Study selection, writing and review editing.Ugonma Winnie Dozie (UWD): Validation, Study Selection, Interpretation of result.Promise Somtochukwu Chukwuemeka: Study selection, Manuscript writing.

Funding

No funds were received for this study.

Data availability

The Data set from the study are available to the corresponding author upon request.

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.