Impact of the National Breast & Cervical Cancer Early Detection
Program (NBCCEDP) on Breast Cancer Morality: Estimating the
Life-Years Saved in Medically Underserved Populations
Donatus U. Ekwueme, PhD, MS
Senior Health Economist
Division of Cancer Prevention and Control
Presentation at the AcademyHealth
2009 Annual Research Meeting
June 28, 2009
Acknowledgement of Co-authors
Thomas J. Hoerger, PhD
Jacqueline W. Miller, MD
Vladislav Uzunangelov, MS
Ingrid J. Hall, PhD, MPH
Joel Segel, BA
Janet Royalty, MS
James G. Gardner, MSPH
Judith W. Lee, PhD
Chunyu Li, PhD, MD
Disclaimer
The findings and conclusions in this report are
those of the authors and do not necessarily
represent the official position of the CDC
Background
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The National Breast and Cervical Cancer Early Detection Program (NBCCEDP)
is the largest cancer screening program in the United States
Established in 1990 by the US Congress
Provides free breast and cervical cancer screening and diagnostic services to
low-income, uninsured, and underinsured women
Administrated by the Centers for Disease Control and Prevention (CDC)
 All the 50 states
 The District of Columbia

5 US territories
 12 American Indian/Alaska Native tribal organizations
Background (Cont’d)
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Eligibility
 At or below 250% of the federal poverty level
 Ages 40-64 years for breast cancer screening
Direct clinical services provided
 Clinical breast examinations
 Mammograms
 Diagnostic testing for women with abnormal screening results
 Surgical consultation
 Referrals to treatment
Non-direct clinical services
 Public education/outreach
 Professional education
 Coalition and partnership
Characteristics of Women Receiving Breast
Cancer Screening within NBCCEDP
Distribution by Race/Ethnicity
Distribution by Age
NBCCEDP Accomplishments: Breast Cancer

Provided screening and diagnostic tests to over 3.3 million women
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Over 8.0 million screening examinations
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Diagnosed over 37,000 breast cancers
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Currently reaching ≤ 15% of the eligible population
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These accomplishments may have saved many lives
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But by how much, when compared with other national programs?
Objective
To estimate the life-years saved by NBCCEDP breast cancer
screening compared with no program and with no screening
Methods
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Reviewed 7 simulation models of breast cancer screening
The Cancer Intervention and Surveillance Modeling Network (CISNET)
(Feuer, JNCI 2006)
Selected the Stanford University model (Plevritis et al., 2006) (henceforth
referred to as “the Stanford model”)
The Stanford model includes:
 natural history module
 screening history module
 breast cancer mortality
 early detection and treatment effects
 other-cause mortality
We modified the screening module to reflect screening frequency for
women receiving NBCCEDP screening
Methods (Cont’d)
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Used 1991-2006 data from the NBCCEDP surveillance database
Estimated the age of first mammography and intervals between
mammograms for women who participated in the Program
We used the 1990-2005 National Health Interview Survey data on
mammograms among uninsured women to represent what would have
happened in the absence of the Program
We performed separate Monte Carlo simulations for women who are
eligible in the NBCCEDP under 3 scenarios:
1) Those who received screening in the NBCCEDP
2) Women who potentially received screening in the absence of the program
(No Program)
3) Women who received no screening at all (No Screening)
Methods: Calculation of Life-Years Saved
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Our analysis covered women who received mammograms from the
NBCCEDP between 1997 and 2006
NBCCEDP database was not complete prior to 1997
We estimated LYs saved by the program for the entire period from 1991 to
2006 and for their remaining lifetime
We performed separate Monte Carlo simulations for:
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women who received screening in NBCCEDP (Program)
women who potentially received screening in the absence of the program (No
Program)
women who received no screening at all (No Screening)
To estimate mean values and confidence intervals for LYs saved, we
simulated 1,000 samples with 100,000 women per sample
Methods: Calculation of Life-Years Saved
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We multiplied the percentage of cancers detected in the simulation by 1.8
million women
The effect of NBCCEDP was estimated as the difference in LYs between the
Program and No Program
We also calculated the difference in LYs between the Program and No
Screening
To calculate 95% confidence intervals for LYs saved, we used a bootstrap
approach, taking the 25th and 975th values from the 1,000 samples
The model was programmed in TreeAge Pro 2008 Suite, version 1.5.1 (TreeAge
Software Inc, Williamstown, MA, USA)
Table 1. Results
Program
No Program
No Screening
1,800,000
1,800,000
1,800,000
Mamm/woman (lifetime)
17.16
12.37
0
Mamm/woman (age 40-64,
1991-2006)
Invasive cancers (both screen
and clinically detected
4.26
2.44
0
248,605
247,743
241,988
13.8%
13.8%
13.4%
Invasive cancers (if no
screening)
241,988
241,988
241,988
Screen detected cancers
141,302
114,024
0
Overall rate
Cancers screen-detected
during program eligibility
7.9%
6.3%
0.0%
28,851
18,596
0
# Women
Overall rate
Table 2. Screen and clinically detected cancers
by stage
Program
No Program
No Screening
Local
76.3%
74.9%
-
Regional
22.1%
23.3%
-
1.6%
1.8%
-
Local
53.3%
51.7%
48.2%
Regional
40.9%
42.1%
44.6%
Distant
5.8%
6.2%
7.2%
Distribution of screen
detected cancers
Distant
Distribution of clinically
detected cancers
Table 3. Mortality
Program
No Program
No Screening
Died of breast cancer
3.7%
4.0%
5.00%
Age at death
80.57
80.52
80.36
Life-year (LY) saved total (vs No Program)
100.800
-
-
LY saved total (vs No Screening)
370,800
270,000
-
LY saved/woman (vs No Program)
0.056
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LY saved/woman (vs No Screening)
0.205
0.150
-
LY saved/woman (vs No Program)
0.41
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LY saved per woman (vs No Screening)
1.49
1.09
-
LY saved/woman (vs No Program)
0.71
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LY saved per woman (vs No Screening)
2.62
2.37
-
Gains for all women
Gains for women with breast cancer
Gains for women with screen detected
cancers
Table 4. Life-Years Saved per Woman in the Program, No Program,
and No Screening Scenarios and 95% Confidence Intervals
Program
No Program
No Screening
Life-year saved
0.056
0.206
0.150
95% confidence
intervals
0.031–0.081
0.177–0.234
0.120–0.177
Discussion
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0.06 years/woman may not seem like a lot, but…
 It’s pretty good for a national program such as NBCCEDP
 Gains/woman with invasive cancer are much higher (0.41 years vs
No Program) or ~150 days
 Gains/woman with screen-detected cancer are even higher (0.71
years vs No Program)
Why not more?
 Most women don’t get breast cancer
 Regular screening will not detect all cancers
 Not all women with breast cancer die in absence of screening
 Some screen-detected, women still die
Table 5. Life Years Gained From Selected
Population-based Prevention Programs
Intervention
Target population
Quitting cigarette smoking
35 year-olds
Gain in Life
expectancy (Life-yrs)
0.667 – 0.833
Pap smear, every year for 55 20 year-old women
years
0.267
Annual fecal occult-blood
test, plus barium enema or
colonoscopy
10 years of biennial
mammography
NBCCEDP (Program vs. No
Program)
50 year-olds
0.183 – 0.208
50 year-old women
0.067
Measles vaccine
Infants
0.008
Rubella vaccine
Infants
0.008
Wright, JC and Weinstein, MC, 1998
Low income, uninsured
0.056
women, starting at age 40 to 64
Limitations
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It’s a simulation model
 Dependent on assumptions about disease progression
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Lack of final outcome data through long-term follow-up
Analysis assumes that NBCCEDP participants whose cancers are detected
receive the same treatment as women in the general population
Results show only LYs gained, and do not include gains from reductions in
morbidity
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For example, morbidity effects might increase the QALYs gained by NBCCEDP
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We only included gains from non-symptomatic testing
Conclusions
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We estimate that mammography screening in the NBCCEDP from 19912006 has saved 100,800 life-years
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Does not include life-years saved through symptomatic testing
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Currently, only about 15% of eligible women are receiving screening
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If the number of women served by the Program were to double, simple
multiplication of our findings suggests that LYs would increase by
100,800 years
Our analysis only includes the direct effects of NBCCEDP on breast
cancer survival
Therefore, the results reported in this paper may be conservative
Thank You!!
Contact information:
Donatus U. Ekwueme, PhD
dce3@cdc.gov
770-488-3182