Do African American Men Have Lower Survival From Prostate Cancer Compared With White Men? A Meta-analysis

Abstract

Prostate cancer is the second leading cause of cancer-related mortality in men. This meta-analysis was conducted to investigate the relationship between race and survival from prostate cancer. A systematic review of articles published from 1968 to 2007 assessing survival from prostate cancer was conducted. Analysis of unadjusted studies reported that African American men have an increased risk of all-cause mortality (hazard ratio [HR] = 1.47, 95% confidence interval [CI] = 1.31-1.65, p < .001). However, examination of adjusted studies identified no difference (HR = 1.07, 95% CI = 0.94-1.22, p = .308). No statistically significant difference was observed in prostate cancer-specific survival in both analyses using unadjusted (HR = 1.11, 95% CI = 0.94-1.31, p = .209) and adjusted studies (HR = 1.15, 95% CI = 0.95-1.41, p = .157). This meta-analysis concludes that there are no racial differences in the overall and prostate cancer-specific survival between African American and White men.

Letter to the Editor

“…There is some overlap between a study of data from the San Francisco Bay region during 1973-1993 (Robbins, Whittemore, & Thom, 2000) and a study of four SEER centers including San Francisco during 1987-1991(OakleyGirvan et al, 2003, with both studies being based on all men with prostate cancer. But we do not see how such limited overlap in the data used by these four studies justifies the exclusion of Polednak (2003), Robbins et al (2000), and Oakley-Girvan et al (2003) and the consequent loss of unique information from the Sridhar et al (2010) analysis. Stepping back from the detail, we would hope that it is uncontroversial to say that the incorporation of overlapping cohort studies within a meta-analysis is not straightforward.…”

“…We did include several studies based on Surveillance, Epidemiology and End Results (SEER) data in our primary analysis (http://seer.cancer.gov/), but we also omitted several others to avoid a large overlap in the data used (Evans et al, 2008). As a result, there was only limited overlap in the data used in the SEER-based studies we included, as can be seen from the brief details given in Table 7 of Sridhar et al (2010). The two more recent studies use data from 1988 to 1997 (Polednak, 2003) and 1992 to 1999 (Du et al, 2006), but the former includes men diagnosed with advanced prostate cancer and the latter men diagnosed with local-or regional-stage prostate cancer.…”

“…Sridhar et al (2010) justify publication of their article by the claim that they have corrected a serious methodological flaw in our analysis. In addition, the reader might expect the Sridhar et al review to include articles published since we conducted our literature search in 2007.…”

“…Unfortunately, on neither count does the Sridhar et al article move forward from our earlier work. Sridhar et al (2010) claim that our analysis has "a major methodological drawback" in that "the authors have included more than one article from the same SEER cancer registry data." We did include several studies based on Surveillance, Epidemiology and End Results (SEER) data in our primary analysis (http://seer.cancer.gov/), but we also omitted several others to avoid a large overlap in the data used (Evans et al, 2008).…”

“…The resulting estimate of the effect of race on prostate cancer-specific case-fatality proved robust in our sensitivity analyses, including one analysis from which the two larger SEER-based studies were omitted (Du et al, 2006;Polednak, 2003). Sridhar et al (2010) searched for articles published up to and including 2007, a slight advance on our search conducted in April 2007 of articles published up to and including 2006 (Evans et al, 2008). Despite this the Sridhar et al (2010) meta-analysis does not include any new data published since our literature search, differences being limited to the choices made between articles based on the same cohorts.…”