Background
Ethnic minority groups in the UK have poorer cancer survival than British White groups. We need better ways to diagnosed cancer in these groups, to improve that. In the UK, cancer is usually diagnosed after someone goes to their doctor with symptoms. The doctor can use blood tests to find out if the patient might have cancer. Lots of blood test results are naturally different between people of different ethnic groups. However, research and advice for doctors on how to use those tests doesn't vary by ethnic group.
Aim
This research aims to find out if blood tests used by doctors to find out if people have cancer vary between people of different ethnic groups.
Methods
We will use observational data on blood test results and cancer diagnoses in people of the following ethnic groups: Black, White, Asian, Mixed, or Other. Blood test results we will study are: platelet count, haemoglobin/mean cell volume, cancer antigen
125 (Ca125), creatine reactive protein (CRP), prostate specific antigen (PSA), and serum calcium. Mathematical techniques will be used to find out the blood test result differs according to ethnicity, when patients have cancer.
How the results of this research will be used
The research will give us detailed knowledge of when the results of standard blood tests might by affected by an undiagnosed cancer in people of different ethnic groups. This information will help doctors to find out if patients have cancer, possibly sooner, when the cancer is easier to treat.
Background
Ethnic minority groups in the UK have poorer cancer outcomes than British White groups. Improving cancer detection strategies for this population may improve outcomes and reduce health inequality. Most cancers are diagnosed following primary care consultation; general practitioners have access to blood tests used in the selection of patients for investigation for possible cancer. Despite evidence of differences in blood test reference ranges in different ethnic groups, research and guidance on these tests do not account for ethnicity.
Research question
Do blood test results used to identify possible cancer in primary care vary between people of different ethnic groups, in terms of their usefulness to predict cancer?
Methods
Cohort study with linked NCRAS&HES data to determine the incidence of cancer in people of Black, White, Asian, Mixed, or Other ethnicities following one of the following abnormal blood test results in primary care: platelet count, haemoglobin/mean cell volume, cancer antigen 125 (Ca125), creatine reactive protein (CRP), prostate specific antigen (PSA), and serum calcium. Sub-cohorts will be derived for each test. The outcome measure will be cancer in the year following that test. Multi-level logistic regression models will be constructed for each sub-cohort, including an interaction term for ethnic group, which will indicate if the effect of the test result differs by ethnicity. We will estimate the positive predictive values for cancer for each ethnic group.
How the results of this research will be used
These results will enable more precise estimates of cancer risk in patients with abnormal blood test results, which will contribute to better diagnosed work-up in primary care and better selection of patients for further investigation for suspected cancer. These results will be used to inform primary care cancer detection practice and policy, such that clinical recommendations will take ethnic differences in cancer risk into account.
Incident cancer in the year following index date for each test, as determined by recorded ICD10 codes (C00-C97). Incident cancer will be the patient's first record of this cancer in their history.
Sarah Bailey - Chief Investigator - University of Exeter
Sarah Bailey - Corresponding Applicant - University of Exeter
Liz Down - Collaborator - University of Exeter
Luke Mounce - Collaborator - University of Exeter
Melissa Barlow - Collaborator - University of Exeter
Rebecca Ward - Collaborator - University of Exeter
Sam Merriel - Collaborator - University of Exeter
Tanimola Martins - Collaborator - University of Exeter
William Hamilton - Collaborator - University of Exeter
Mike Cooke - Collaborator - University of Exeter
HES Admitted Patient Care;NCRAS Cancer Registration Data;No additional NCRAS data required;Patient Level Index of Multiple Deprivation