Investigating Black‐White differences in prostate cancer prognosis: A systematic review and meta‐analysis

Abstract

The case-fatality rate following a diagnosis of prostate cancer is higher for Black men compared to White men. How this elevated rate arises is uncertain, with differences in disease biology, presentation, treatment and comorbidity having been suggested. A systematic search was conducted for articles that reported ethnic differences in overall-survival, prostate cancer specific survival (PSS) or biochemical recurrence. 48 articles met the inclusion criteria. Black men had worse overall survival (risk ratio 1.35, 95% CI 1.23-1.48) but this was not due to comorbidity alone as PSS and risk of biochemical recurrence were also elevated (1.29, 95% CI 1.13-1.47 and 1.34, 95% CI 1.23-1.46, respectively). Studies adjusting for clinical predictors and socioeconomic variables no longer supported a difference in overall survival (1.01, 95% CI 0.88-1.16), but continued to find an increased risk amongst Black men for PSS (1.13, 95% CI 1.00-1.27) and biochemical recurrence (1.25, 95% CI 1.11-1.41). Similar results were seen for studies from the pre-PSA era and free-health care settings. In contrast to others, studies of metastatic cancer did not find evidence of BlackWhite differences (p for interaction 5 0.01). In conclusion, Black men had a poorer prognosis which was not fully explained by comorbidity, PSA screening, or access to free health care, although few studies measure these factors well. Either management differences for local disease and/or biological differences may be behind Black-White differences in prostate cancer prognosis. ' 2008 Wiley-Liss, Inc.Key words: prostate cancer; ethnicity; prognosis; meta-analysis It is relatively uncontroversial to state that Black men have a greater incidence of prostate cancer than white men.1-3 The picture is less clear with regards ethnic differences in case fatality following prostate cancer diagnosis. There are several reasons why Black men may have a worse prognosis than their White counterparts.4,5 Some of these reasons may reflect socio-cultural differences that are amenable to intervention, whilst others may reflect genuine racial differences in cancer biology. These 2 types of explanations are not mutually exclusive and both may operate simultaneously.Possible socio-cultural explanations are: (i) Black men may have worse access to health care and therefore present later in the natural history of the disease at a more advanced stage. 6 (ii) In the US, more White men in the past have been diagnosed through screening.7 This will artefactually increase survival differences due to the phenomena of ''lead-time'' and ''length-time'' biases. (iii) Black men may be subject to differences in clinical management such that they are less aggressively investigated or treated. 8,9 (iv) Black men are more likely to have lower socioeconomic status, increased comorbidity and overall reduced life-expectancy compared to White men.10 These factors will increase the apparent difference in mortality rates even if there were no ethnic differences in the natural history of prostate cancer. How...

Population differences in microRNA expression and biological implications

“…Population differences have been observed in many human complex traits, including disease susceptibility, 29,30 drug sensitivity 31,32 and gene expression. [6][7][8] Genetic polymorphisms have undergone extensive evaluation for their potential role in these observed expression may contribute to observed population differences in mRNA expression levels and possibly other complex human traits.…”

Controversial predictors of biochemical recurrence after radical prostatectomy: a study from a Latin American (Brazilian) Institution

“…Prostate cancer may be biologically more aggressive among Black men though controversial (7)(8)(9). In a study by Cross et al (10), even though African-American men presented at a younger age and with more advanced disease compared with White men with prostate cancer, PSA outcome after RP when controlled for known clinical predictive factors was not statistically different.…”

“…Prostate cancer may be biologically more aggressive among Black men though controversial (7)(8)(9)(10)(11). The prevalence of prostate cancer in Brazil is higher in Black men compared to White men (12)(13)(14)(15).…”

Ethnic differences in patients’ preferences for prostate cancer investigation: a vignette-based survey in primary care

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