Differences in Prognostic Factors and Survival among White Men and Black Men
with Prostate Cancer, California, 1995–2004
Anthony S. Robbins, Daixin Yin, and Arti Parikh-Patel
From the California Cancer Registry, Public Health Institute, Sacramento, CA.
Received for publication October 4, 2006; accepted for publication January 5, 2007.
The authors conducted a study to determine whether differences in prostate cancer survival between White men
and Black men are reduced or eliminated after accounting for differences in prognostic factors. Using population-
based statewide cancer registry data, the authors analyzed data from a cohort of 122,375 non-Hispanic White men
and Black men from California who were newly diagnosed with prostate cancer between 1995 and 2004 and
followed through 2004. Compared with White men, Black men were characterized by younger age at diagnosis,
more distant stage, less treatment with surgery or radiation therapy, higher tumor grades, lower neighborhood
socioeconomic status, and more recent year of diagnosis. Adjusted only for age, the hazard ratio for prostate
cancer death (Blacks vs. Whites) was 1.61 (95% confidence interval (CI): 1.50, 1.72). Additional adjustment for
potentially modifiable factors (stage and treatment) eliminated most of the racial difference in survival (adjusted
hazard ratio ¼ 1.10, 95% CI: 1.03, 1.18). The racial difference in survival was completely eliminated after further
adjustment for other factors (grade, socioeconomic status, and year of diagnosis) (adjusted hazard ratio ¼ 0.99,
95% CI: 0.92, 1.06). Thus, the large difference in prostate cancer survival between White men and Black men was
completely explained by known prognostic factors, with potentially modifiable disparities playing the largest role.
African Americans; carcinoma; ethnology; prostatic neoplasms; registries; survival analysis
Abbreviations: AJCC, American Joint Committee on Cancer; CI, confidence interval; HR, hazard ratio; ICD-O-2, International
Classification of Diseases for Oncology, Second Edition; SEER, Surveillance, Epidemiology, and End Results.
Prostate cancer exhibits some of the largest differences
between Whites and Blacks in incidence, mortality, and
survival seen for any cancer site (1). These differences have
of geographic regions and different health-care delivery sys-
tems. Some factors offered as potential explanations for
survival disparities between White men and Black men in-
clude differences in patient characteristics (age, competing
causes of death, socioeconomic status, genetic factors), tu-
mor characteristics (stage, grade), and treatment. The ques-
tion of whether racial differences in prostate cancer survival
can be explained by known risk factors has major public
health and research implications but has not been settled,
with roughly half the studies concluding that the differences
can be explained and half concluding that they cannot
(2–24). For example, one study found that racial survival
differenceswereeliminated amongmen treated withsurgery
(11), while another reported that racial differences were
greatest among men treated with surgery (14). Limitations
that is, pre-1988 cases; restrictions by age and stage; lack of
data on treatment or cause of death; and use of small or non-
and after 1988 is not advisable, because of the dramatic
changes in incidence, stage, grade, and survival seen after
the introduction of prostate-specific antigen screening.
A meta-analysis published in 2002 examined racial sur-
vival differences for all major cancer sites and attempted to
Correspondence to Dr. Anthony S. Robbins, California Cancer Registry, 1700 Tribute Road, Suite 100, Sacramento, CA 95815-4402
71 Am J Epidemiol 2007;166:71–78
American Journal of Epidemiology
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2. Freeman VL, Durazo-Arvizu R, Keys LC, et al. Racial differ-
ences in survival among men with prostate cancer and comor-
bidityat time of diagnosis. Am J Public Health 2004;94:803–8.
3. Merrill RM, Brawley OW. Prostate cancer incidence and
mortality rates among white and black men. Epidemiology
4. Makridakis N, Ross RK, Pike MC, et al. Association of mis-
sense substitution in SDR5A2 gene with prostate cancer in
African-American and Hispanic men in Los Angeles, USA.
5. Jepson C, Kessler LG, Portnoy B, et al. Black-white differ-
ences in cancer prevention knowledge and behavior. Am J
Public Health 1991;81:501–4.
6. Myers RE, Wolf TA, Balshem AM, et al. Receptivity of
African-American men to prostate cancer screening. Urology
7. Harlan L, Brawley O, Pommerenke F, et al. Geographic, age
and racial variation in the treatment of local/regional
carcinoma of the prostate. J Clin Oncol 1995;13:93–100.
8. Blendon RJ, Aiken LH, Freeman HE, et al. Access to care for
black and white Americans: a matter of cost concern. JAMA
9. Pienta KJ, Demers R, Hoff M, et al. Effect of age and race on
the survival of men with prostate cancer in the metropolitan
Detroit tri-county area, 1973–1987. Urology 1995;45:93–101.
10. Powell IJ, Schwartz K, Hussain M. Removal of the financial
barrier to health care: does it impact on prostate cancer at
presentation and survival? A comparative study between black
and white men in a Veterans Affairs system. Urology 1995;
11. Tewari A, Horninger W, Pelzer AE, et al. Factors contributing
to the racial differences in prostate cancer mortality. BJU Int
12. Klabunde CN, Potosky AL, Harlan LC, et al. Trends and
black/white differences fornonmetastatic prostate cancer. Med
13. Sohayda CJ, Kupelian PA, Altsman KA, et al. Race as an
independent predictor of outcome after treatment for localized
stage prostate cancer. J Urol 1999;162:1331–6.
14. Godley PA, Schenck AP, Amamoo A, et al. Racial differences
in mortality among Medicare recipients after treatment for
localized prostate cancer. J Natl Cancer Inst 2003;95:1702–10.
15. Hoffman RM, Gilliland FD, Eley JW, et al. Racial and ethnic
differences in advanced-stage prostate cancer: the Prostate
Cancer Outcomes Study. J Natl Cancer Inst 2001;93:388–95.
16. Thompson I, Tangen C, Tolcher A, et al. Association of
African-American ethnic background with survival in men
with metastatic prostate cancer. J Natl Cancer Inst 2001;93:
17. Fowler JE Jr, Terrell F. Survival in blacks and whites after
treatment for localized prostate cancer. J Urol 1996;156:
18. Fowler JE Jr, Braswell NT, Pandey P, et al. Experience with
radical prostatectomy and radiation therapy for localized
prostate cancer at a Veterans Affairs Medical Center. J Urol
19. Roach M 3rd, Krall J, Keller JW, et al. The prognostic sig-
nificance of race and survival from prostate cancer based on
patients irradiated on Radiation Therapy Oncology Group
protocols (1976–1985). Int J Radiat Oncol Biol Phys 1992;
20. Brawn PN, Johnson EH, Kuhl DL, et al. Stage at presentation
and survival of white and black patients with prostate carci-
noma. Cancer 1993;71:2569–73.
21. Optenberg SA, Thompson IM, Friedrichs P, et al. Race,
treatment, and long-term survival from prostate cancer in an
equal-access medical care delivery system. JAMA 1995;274:
22. Robbins AS, Whittemore AS, Van Den Eeden SK. Race,
prostate cancer survival, and membership in a large health
maintenance organization. J Natl Cancer Inst 1998;90:986–90.
23. Lu-Yao GL, Friedman M, Yao SL. Use of radical prostatec-
tomy among Medicare beneficiaries before and after the
introduction of prostate specific antigen testing. J Urol 1997;
24. Robbins AS, Whittemore AS, Thom DH. Differences in
socioeconomic status and survival among White and Black
men with prostate cancer. Am J Epidemiol 2000;151:409–16.
25. Bach PB, Schrag D, Brawley OW, et al. Survival of blacks
and whites after a cancer diagnosis. JAMA 2002;287:
26. US Census Bureau. State and county quickfacts: California.
Washington, DC: US Census Bureau, 2006. (http://quick-
facts.census.gov/qfd/states/06000.html). Accessed July 19,
27. Yost K, Perkins C, Cohen R, et al. Socioeconomic status and
breast cancer incidence in California for different race/ethnic
groups. Cancer Causes Control 2001;12:703–11.
28. Stanford JL, Stephenson RA, Coyle LM, et al, eds. Prostate
cancer trends 1973–1995, SEER Program, National Cancer
Institute. Bethesda, MD: National Cancer Institute, 1999.
(NIH publication no. 99-4543).
29. Marubini E, Valsecchi MG. Analysing survival data from
clinical trials and observational studies. Chichester, West
Sussex, England: John Wiley & Sons, Ltd, 1995.
30. Penson DF, Albertsen PC, Nelson PS, et al. Determining cause
of death in prostate cancer: are death certificates valid? J Natl
Cancer Inst 2001;93:1822–3.
31. Gilligan T, Wang PS, Levin R, et al. Racial differences in
screening for prostate cancer in the elderly. Arch Intern Med
32. Liu WL, Kasl S, Flannery JT, et al. The accuracy of prostate
cancer staging in a population-based tumor registry and its
impact on the black-white stage difference (Connecticut,
United States). Cancer Causes Control 1995;6:425–30.
33. Polednak AP. Black-white differences in tumor grade (ag-
gressiveness) at diagnosis of prostate cancer, 1992–1998. Ethn
34. Freeman VL, Leszczak J, Cooper RS. Race and the histologic
grade of prostate cancer. Prostate 1997;30:79–84.
35. Frankel S, Davey Smith G, Neal D. Screening for prostate
cancer. Lancet 2003;361:1122–8.
78 Robbins et al.
Am J Epidemiol 2007;166:71–78
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