Studying Cancer in Minorities
A Look at the Numbers
Sara H. Olson, PhD1; Tracy M. Layne, MPH1; Jennifer A. Simon, MA1; Emmy Ludwig, MD2; Eileen O’Reilly, MD2;
Peter J. Allen, MD3; and Robert C. Kurtz, MD2
BACKGROUND: Inclusion of minorities is an important but challenging aspect of epidemiologic studies in the United
States. One aspect of this challenge that has received little attention is the actual number of minorities with specific
cancers. The authors aimed to understand how population characteristics affect the numbers of minority cancer
cases in Surveillance, Epidemiology, and End Results (SEER) regions. METHODS: By using SEER data, the authors
identified 6 cancers with higher incidence rates in racial and ethnic minorities and reviewed the annual number of
cases of those cancers in SEER areas where there are large numbers of blacks, Hispanics, and Asians. The authors
examined the age characteristics of the populations in SEER areas using data from the US Census. RESULTS:
Although there are substantial numbers of cases for the most common cancers with higher incidence in blacks, their
numbers are quite small for other cancers, <150 cases, and in many areas, <100 per year. Few registries have substan-
tial numbers of Hispanics or Asians. As expected, the proportion of minority populations is lower in older age groups,
whereas the proportion of non-Hispanic whites is larger. CONCLUSIONS: Because of the sharp decline in minority
populations associated with age and the high age-specific incidence rates of most cancers, the actual number of
minority cases is quite small for several cancers. Thus, the inclusion of minority groups in studies of any but the most
common cancers presents a challenge. Cancer 2011;117:2762–9. V
C 2011 American Cancer Society.
KEYWORDS: cancer, minorities, minority recruitment, epidemiology, population characteristics.
Epidemiologists attempt to include racial and ethnic minorities in their studies to obtain a study population
that reflects the source population. For a more complete understanding of the sources of health disparities, we are
particularly concerned with including minorities in studies of those diseases that have higher incidence rates in minor-
ities. In an earlier study of pancreatic cancer in New York City in which we had relatively few blacks enrolled, we inves-
tigated the actual numbers of black cases in the area, which we found to be surprisingly small in light of the large
minority population in this area and the higher incidence of pancreatic cancer in blacks. This investigation was
expanded to other cancers that have higher age-adjusted incidence rates in blacks and other minorities and to
Surveillance, Epidemiology, and End Results (SEER) registry areas to gain an understanding of how age adjustment
and age distribution affect the practical aspects of including minority groups in epidemiologic studies. We focused on
SEER areas because epidemiologic studies are frequently conducted in these geographically defined areas and because
source population data are available.
MATERIALS AND METHODS
By using data from the American Cancer Society,1we identified the most common cancers in the United States in 2004,
choosing this year as the midpoint of the period for which recent data on numbers of cases were available (2002-2006)
from the SEER Cancer Statistics Review 1975-2006.2We limited our analysis to 14 cancers with at least 20,000 cases in
total. These cancers (and the numbers diagnosed in 2004, in thousands) were prostate (230), lung/bronchus (173), breast
(215), colorectal (147), bladder (60), non-Hodgkin lymphoma (54), melanoma (55), kidney/renal pelvis (35),
DOI: 10.1002/cncr.25871, Received: July 22, 2010; Revised: November 9, 2010; Accepted: November 29, 2010, Published online January 10, 2011 in Wiley
Online Library (wileyonlinelibrary.com)
Corresponding author: Sara H. Olson, PhD, Memorial Sloan-Kettering Cancer Center, 307 East 63rd Street, New York NY 10065; Fax: (646)735-0012;
1Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York;2Department of Medicine, Memorial Sloan-Ketter-
ing Cancer Center, New York, New York;3Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
June 15, 2011
1. American Cancer Society, eds. Cancer Facts and Figures
2004. Atlanta, GA: American Cancer Society; 2004.
2. Horner MJ, Ries LAG, Krapcho M, et al, eds. SEER Cancer
Statistics Review, 1975-2006. Bethesda, MD: National
2006/, based on November 2008 SEER data submission,
posted to the SEER web site, 2009.
Program SEER*Stat Database: Incidence-SEER 17 Regs
Limited-Use þ Hurricane Katrina Impacted Louisiana
Cases, Nov 2007 Sub (2000-2005) <Katrina/Rita Popula-
tion Adjustment>Linked to County Attributes-Total U.S.,
1969-2005 Counties, National Cancer Institute, DCCPS,
Surveillance Research Program, Cancer Statistics Branch,
released April 2008, based on the November 2007 submis-
sion. 2008. www.seer.cancer.gov
4. US Bureau of Census, Census 2000, Summary File 1, Table
5. NAACCR Expert Panel in Hispanic Identification. Report
of the NAACCR Expert Panel on Hispanic Identification
2003. Springfield, IL: North American Association of
Central Cancer Registries; October 2003.
6. United States Department of Health and Human Services,
Centers for Disease Control and Prevention, National
Center for Health Statistics (NCHS). Bridged-Race Popula-
tion Estimates, United States July 1st resident population by
state, county, age, sex, bridged-race, and Hispanic origin,
compiled from 1990-1999 bridged-race intercensal popula-
tion estimates and 2000-2006 (Vintage 2006) bridged-race
postcensal population estimates: CDC WONDER On-
line Database. http://wonder.cdc.gov/Bridged-Race-v2006.
7. Hamilton BE, Martin JA, Ventura SJ. Births: Preliminary
data for 2007. National Vital Statistics Reports. Hyattsville,
MD: National Center for Health Statistics; 2009.
8. Murray CJ, Kulkarni SC, Michaud C, et al. Eight Americas:
investigating mortality disparities across races, counties, and
race-counties in the United States. PLoS Med. 2006;3:e260.
9. Fix M, Passel JS. U.S. Immigration—Trends & Implica-
tions for Schools. In: Institute ISPTU, ed. National Associa-
and End Results (SEER)
tion for Bilingual Education. New Orleans, LA: NCLB
Implementation Institute; 2003:32.
10. Jemal A, Thun MJ, Ries LA, et al. Annual report to the
nation on the status of cancer, 1975-2005, featuring trends
in lung cancer, tobacco use, and tobacco control. J Natl
Cancer Inst. 2008;100:1672-1694.
11. Sweeney C, Edwards SL, Baumgartner KB, et al. Recruiting
Hispanic women for a population-based study: validity of
surname search and characteristics of nonparticipants. Am J
12. Ashing-Giwa KT, Padilla GV, Tejero JS, Kim J. Breast can-
cer survivorship in a multiethnic sample: challenges in
recruitment and measurement. Cancer. 2004;101:450-465.
13. Moorman PG, Newman B, Millikan RC, Tse CK, Sandler
DP. Participation rates in a case-control study: the impact
of age, race, and race of interviewer. Ann Epidemiol.
14. Ambrosone CB, Jandorf L, Furberg H, Britton JA, Bovbjerg
DH, Erwin DO. Re: ‘‘Population- and community-based
recruitment of African Americans and Latinos: the San
Francisco Bay Area Lung Cancer Study’’. Am J Epidemiol.
15. Cabral DN, Napoles-Springer AM, Miike R, et al. Population-
and community-based recruitment of African Americans and
Latinos: the San Francisco Bay Area Lung Cancer Study. Am J
16. Larkey LK, Gonzalez JA, Mar LE, Glantz N. Latina recruit-
ment for cancer prevention education via Community Based
Participatory Research strategies. Contemp Clin Trials. 2009;
17. Paskett ED, DeGraffinreid C, Tatum CM, Margitic SE.
The recruitment of African-Americans to cancer prevention
and control studies. Prev Med. 1996;25:547-553.
18. Pham B, Earle N, Rabel K, Follen M, Scheurer ME. Maxi-
mizing the diversity of participants in a phase II clinical trial
of optical technologies to detect cervical neoplasia. Gynecol
Oncol. 2007;107(1 suppl 1):S208-S214.
19. Zhu K, Hunter S, Bernard LJ, Payne-Wilks K, Roland CL,
Levine RS. Recruiting elderly African-American women in
cancer prevention and control studies: a multifaceted approach
and its effectiveness. J Natl Med Assoc. 2000;92:169-175.
Cancer in Minorities/Olson et al
June 15, 2011