African Americans: To screen earlier? Chyke Doubeni, MD, FRCS, MPH

Transcription

1 African Americans: To screen earlier? Chyke Doubeni, MD, FRCS, MPH Department of Family Medicine and Community Health Perelman School of Medicine Senior Scholar, Center for Clinical Epidemiology and Biostatistics University of Pennsylvania Gates 2, 3400 Spruce Street Philadelphia, PA 19104

2 Race-Specific Screening Guidelines ACG guidelines recommend screening African American men and women for CRC beginning at age 45* There is no strong premise for this recommendation A weak recommendation [based on] lowquality or very low-quality evidence Should other groups adopt this policy? *Rex et al. Am J Gastroenterol 2009;104: Siegel RL, Miller KD, Jemal A. CA Cancer J Clin

3 New Cases per 100,000 CRC Disparities in the US, SEER Number of New Cases per Year 35 Number of Deaths per Year White Black Asian/Pacific Islander Hispanics

4 African Americans Compared with Whites Adenoma Larger adenomas (>9mm) 1 Similar prevalence of adenomas 2 Age (SEER ) Proximal cancers (SEER ) Stage Screening Diagnostic testing Quality of exam Treatment Survival Somatic Mutations Methylation markers Younger average age at diagnosis 2 Males 63.8 vs years Females 65.7 vs years Males (B) 41-44% vs % Females (B) 47-49% vs % Later stage at presentation Lower screening rate/late adopters Lower likelihood Poorer Lower Lower More favorable prognostic markers CIMP & MSI status equivocal Higher incidence More proximal colon cancers Higher death rate Lower average age at diagnosis African Americans have lower life expectancy 1. Lieberman DA et al. JAMA. 2008; 2. Corley, et al. CGH. 2013; Laiyemo AO, et al. JNCI Agrawal S, et al. AJG Singh S et al. AJG. 2014

5 Should African Americans be Screened Earlier? The epidemiological patterns of CRC are true, but not for the reasons commonly given and therefore the solutions proposed are ill-suited The younger diagnosis age is likely an artifact of epidemiology We could solve this problem by improving life expectancy for African American Earlier age at screening for AAs is not the right answer Race is a social construct and its meaning is changing We should define screening initiation based on disease risk, and race may be a factor Balance the risks, benefits and yield, with resources used in screening Should we then screen based on income levels? We should engage people in screening earlier This is a sound public health approach

6 Knowing an Individual s Disease Risk is the Key to Genetic risks (heritable) AGE We should define a risk threshold for initiating screening This should be based on historical trends Race may be a factor, but probably not the most important A person s CRC (& CVD/cardiometabolic) risk should be defined early and updated regularly starting at no later than age 20: Determine when screening should be initiated Determine if chemoprevention or lifestyle changes are needed

7 That was my opinion! What is the rationale?

8 CRC Incidence by race, sex, and age , SEER 18 Registries

9 CRC Incidence by race, sex, and age , SEER 18 Registries

10 Incidence by race, sex, and age , SEER 13/18 Registries

11 CRC Screening Prevalence by Age, Race and Year, NHIS * *Courtesy Stacey Fedewa, American Cancer Society

12 What would happen if.. Age-standardized CRC mortality rates (50+year old population) as observed for whites and blacks, and as expected for blacks if they would have had the same screening pattern as whites, or the same survival pattern or a combination Cancer Epidemiol Biomarkers Prev May; 21(5):

13 So, it is not all about screening. Survival after Treatment in a Clinical Trial Patients with Stage III CRC in a clinical trial with FOLFOX/EGFR inhibitor therapy No differences in quality of care No black-white difference in 5-yr DFS in patients 50+ >2.5-fold higher risk of death or tumor recurrence in blacks compared with whites in patients <50 years None of the biological markers of prognosis or treatment effect heterogeneity appeared to explain the observed disparities. Doubeni CA, Rustgi A. JNCI Jul 28;107(10) Yoon, et al. JNCI J Natl Cancer Inst (2015) 107 (10)

14 Just because you can screen, does not mean you should Disease/condition Characteristics of disease Predictive value or yield Probability of disease given a positive result It depends on disease prevalence Optimized by targeting groups at increased risk Test result T+ D+ D- TP FP T- FN TN Characteristics of the test 1. Sensitivity probability of a positive test in the population with the condition 2. Specificity probability of negative given absence of condition 3. Spectrum effect is possible 4. Quality of the test

15 Incidence, True Positives, and Positive Predictive Value for Colonoscopy # for CRC (race, sex & age) Incidence and True Positives Positive Predictive Value 150 0,125 Females (45) Males (45) ,100 0,075 Females (50) Males (50) Females (60) Males (60) , ,025 0 Inc (W) TP (W) Inc (B) TP (B) 0,000 PVP (W) PVP (B) *INCIDENCE IS per 100,000 Data are from SEER (18 registries) # Assumes 95% sensitivity and 99% specificity

16 Concluding thoughts

17 Proportion of population with disease (RISK) Individual level Awareness Accessibility Affordability Acceptable (choice) SCREENING DETECTION at preclinical phase, fatal if untreated Program/policy TREATMENT is effective at averting death Wilson & Jungner. 1968; Bull WHO 2008; 86(4): ; National Screening Committee, UK; EQUITY: Risk assessment, detection, & treatment Plan follow-up testing at outset Cost and resources for detection and treatment Systems to support continuing screening

18 The CRC screening process and Medicare coinsurance Gastroenterology , DOI: ( /j.gastro ) Copyright 2016 AGA Institute Terms and Conditions

19 Access to information about risk Access to individualized care based on risk Bottom-line Ability or willingness to act on the information Ability or willingness or to use care