Is prostate cancer more common and more aggressive in African men?

A comparison of clinicopathologic features of prostate cancer between Nigerian and South African black men

Background

Globally, prostate cancer (PCa) is the commonest non-cutaneous male malignancy. It is more aggressive among black men with little known reasons as to the cause and continued trend among black men. This disproportionate pattern of PCa especially among black men of African ancestry resident in Africa calls for a closer look. Nigeria and South Africa, combined, have the highest cumulative risk incidence of PCa in Africa. The present study investigated the clinicopathologic behaviour of PCa among Nigerian and South African black men and the relationship between the disease and socio-demographic characteristics alongside medical co-morbidities.

Methods

A retrospective cross-sectional study was undertaken in which de-identified records of 234 black men with pathologically confirmed PCa between 2007 and 2017 from two tertiary hospitals, in Nigeria (National Hospital, Abuja) and South Africa (Tygerberg Hospital, Cape Town), were reviewed.

Results

Median age at presentation from both countries was 66 years (interquartile range, IQR 61–73 years) while the median PSA at presentation was 46 ng/ml (IQR 16–336.5 ng/ml). Half of the men (117/234) presented with locally advanced disease while metastatic disease was observed in 65.9% (27/41) of Nigerian men and 34.1% (14/41) of South African men. Thirty-three per cent of the men presented with organ-confined disease. Overall, Nigerian men presented with less organ-confined disease and significantly higher stage of disease (p < 0.001). Risk stratification using PSA, Gleason scores and T-staging showed that 84.2% (n = 197) of all the men presented with high-risk PCa disease. There was a statistically significant difference between Nigerian and South African black men (p = 0.003) in terms of disease risk at presentation. Logistic regression analysis showed that age (Adjusted OR 1.053 (95% CI 1.003–1.106), p = 0.003) and country of residence (Adjusted OR 4.281 (95% CI 1.690–10.844), p = 0.002) had a statistically significant relationship with high risk of PCa while disease co-morbidities (like diabetes and hypertension) and rural/urban location in both countries did not.

Conclusions

Disparities exist between PCa presentation and clinicopathologic behaviour among Nigerian and South African black men. Nigerian men showed higher disease risk at presentation. Environmental-genetic interactions need further exploration in the aetio-pathogenesis of PCa in black men of African ancestry.

High mortality risk of prostate cancer patients in Asia and West Africa: A systematic review

Globally, prostate cancer (PCa) is the second most preponderant cancer in men. It contributes to the high mortality-to-incidence ratio reported in West Africa and Asia largely due to low screening. The mortality risk is determined or predicted based on the prevalence of high-risk or aggressive PCa using a scoring or grading system such as Gleason score (GS), Gleason grade (GG), and prostate-specific antigen (PSA) level. In this review, peer-reviewed articles found on databases such as Google Scholar, Scopus, Web of Science, PubMed Central and, EMBASE were selected based on adherence to clinical guidelines for the classification of PCa. In West Africa and Asia, the result revealed that the frequency of high-risk PCa was 42% and 51.2% based on GS, 48.8% and 25.3% based on GG pattern, and 87.5% and 44.3% based on PSA level >10 ng/mL, respectively. Data revealed a high prevalence of high-risk PCa both in West Africa and Asia when compared with developed countries. However, the prevalence of high-risk PCa is higher in West Africa than in Asia. Studies have shown that high-risk PCas are associated with germline mutations and such mutations are prevalent in blacks and Asians than in whites. Thus, testing for germline mutations in patients with GS of ≥ 7, GG ≥ 3, high prostate density, low prostate volume, and PSA levels of >4.0 ng/mL may identify those at risk of developing lethal PCa and could reduce the mortality rates in Asia and West Africa.

Prostate cancer among Jamaican men: exploring the evidence for higher risk

BACKGROUND

Historically, black men of African descent have been disproportionately affected by prostate cancer compared with Caucasian men. African-Caribbean men are generally at higher risk of prostate cancer, with Jamaican men noted to have the highest incidence in the world. No robust evidence exists for the increased incidence among Jamaican men, or indeed, a clear explanation for the reasons these men are at a greater risk of developing the disease in comparison with other African-Caribbean men.

METHODS AND FINDINGS

A literature review was undertaken. The findings indicated that black men of African descent, specifically Jamaican men, are at greater risk of prostate cancer and this finding applies to Africa, the Caribbean, the UK and USA.

CONCLUSIONS

Current evidence for the higher incidence of prostate cancer among Jamaican men remains inconclusive and does not provide a clear explanation for its prevalence. More comparative studies are required to identify any predisposing factors responsible for this anomaly, worldwide. The involvement of health professionals in these research undertakings is important to obtaining insight into prostate cancer and in devising strategies to improve management and health outcomes.