Prostate Cancer in Men of African Heritage: Understanding the risk and prognostic factors

Prostate cancer (PCa) represents a major public health concern and recognised as one of the most common cancers worldwide, accounting for a significant proportion of cancer-related deaths. It is the second most common malignancy among men globally after lung cancer. In 2018, there were 1,276,106 new cases of PCa and 358,989 deaths due to it1. In 2020, the global incidence rate was reported by the Global Cancer Observatory to be 1,414,259 with an estimated death rate of 375,304. A rising incidence of PCa was seen in the USA with estimated cases of 268,490 in 2022, the highest among African American men with 183.4 new cases per 100,000 individuals 2. African American men also face an increased risk of developing PCa at all stages of the disease compared to Caucasian men.2
Africa, home to the largest black population globally, has the highest frequency of PCa diagnoses. Numerous studies have reported that among men of African descent, PCa is the dominant cancer in terms of both incidence and mortality.3Data from the International Agency for Research in Cancer in 2018, indicated that the age-adjusted incidence rate of PCa among African men is 845 per 100,000 persons annually. In sub-Saharan Africa, research evidence revealed that the diagnosis of PCa stands at 54 per 100,000 men annually with an estimated death rate of 20 per 1000,000 and a projected death rate of 57,048 by 2030.The annual death rate is expected to rise significantly from 42,298 in 2018 to 94,909 in 2040. A 124.4% rise in the next decade according to WHO, such a rise is greater than those marked for North America (+101.2%), Europe (+58.3%), and Asia (+ 105.6%). There is notable variation in the incidence and mortality of PCa across racial, ethnic, and geographic groups. African American men are 2.04 times more likely to die from PCa than white men. Similarly, the African Caribbean population has also been reported to have the highest incidence of PCa, at 26.3 per 100,000 compared to men of Asian ancestry with a significantly lower rate of 2.5 per 100,000
An earlier age incidence, occurring in men under 55 years, has been reported, with 1 in every 350 men diagnosed in this age group. Previous autopsy reports suggest that 3% of African American men aged 20 to 30 years, 26% of men aged 30 to 39 years, and 50% of men aged 40 and 44 years had evidence of PCa. The reason could be genetic; although the extent remains unclear, it is postulated that BRCA2 carriers have a 23-fold higher risk for PCa at an early age. Africa has also reported a greater incidence rate of PCa in young people and a more aggressive type of disease compared to the high-income countries of the world.
The risk for the disease has been attributed to non-modifiable factors such as age, family history, race, and genetic mutations, as well as modifiable factors like diabetes, obesity, and smoking4. Others include environmental factors, lifestyle changes, infectious diseases, and dietary habits. In Africa, the population genomic, environmental factors, and infectious agents have been identified as the main factors significantly contributing to the increased risk of PCa.
The clinical and economic burden of PCa can be enormous to both the patients and the government5. In the UK, the total annual cost for treatment of the disease was estimated at 117 million pounds, with two-to-three-fold higher figures in France and Germany. It has been reported that the total annual management cost of PCa in Eswatini, a Southern African country is high and estimated to be about 6 million dollars5.