Microcytosis as a risk marker for cancer in primary care: a cohort study using electronic patient records

Talk Code: 
P1.57
Presenter: 
Rhian Hopkins
Co-authors: 
Elizabeth Shephard, Sarah Bailey, Willie Hamilton
Author institutions: 
University of Exeter

Problem

Microcytosis has found to be a risk marker in five cancers. It is not known whether it is also present in other cancer sites. The aim of this study is to investigate the role of microcytosis as a risk marker for all cancers.

Approach

This cohort study uses electronic patient records from the Clinical Practice Research Datalink (CPRD) to study the one-year incidence of cancer in 108,919 patients aged 40 years and over between 2006-2008. Patients were grouped as either: having microcytosis (16,684), macrocytosis (4796); or a normal blood test result (87,439). For comparison, the records of 42,803 patents who did not have a blood test were also examined.

Findings

Preliminary results show that 577 (3.46%) patients with microcytosis were diagnosed with cancer within one year of their test result. For patients with a normal MCV the number was 1941 (2.22%) and 352 (0.82%) for untested patients. The cancers most significantly associated with microcytosis were: colorectal (21.66%), lung (11.79%), lymphoma (4.68%), kidney (3.81%) and stomach (2.60%). Planned sub-analyses will investigate the cancer risk by age-group and gender; the significance of accompanying symptoms will also be associated. Results so far show that the one year cancer incidence for males was 5.06% and females was 2.39%.

Consequences

UK cancer survival lags behind many other European countries. Determining the role of microcytosis as a risk marker for all cancers would help guide clinical decision making, thereby helping to expedite cancer diagnosis.

Submitted by: 
Rhian Hopkins
Funding acknowledgement: