Prevalence of gastrointestinal malignancy in non-anemic iron deficiency and significance for endoscopic screening: A Western Australian multicenter cohort study

Background and AimThere is a paucity of evidence regarding non-anemic iron deficiency as a predictor for colorectal cancer and therefore the indication for endoscopic evaluation. This study explores the rates of malignancy in adults with iron deficiency with and without anemia. MethodsA retrospective multicenter diagnostic cohort study was conducted across two Australian health services. All cases that underwent both esophagogastroduodenoscopy and colonoscopy between September 1, 2018, and December 31, 2019, for the investigation of iron deficiency were included, and the cohort was divided into anemic and non-anemic arms. Multivariate binomial logistic regression was performed to establish clinical characteristics associated with neoplasia. ResultsFive hundred eighty-four patients underwent endoscopic evaluation over a 16-month period. There was a significantly higher rate of malignancy in the iron deficiency anemia arm as compared with those without anemia (8.76% vs 1.20%, P < 0.01). Gastrointestinal pathology to account for iron deficiency was identified in > 60% of the total cohort. The presence of anemia (odds ratio [OR] 6.87, P < 0.01) and male gender (OR 3.01, P = 0.01) were significant predictors of malignancy. ConclusionThis study demonstrates that anemic iron deficiency confers a significantly greater risk of gastrointestinal cancer compared with non-anemic iron deficiency. Additionally, over 60% of patients had gastrointestinal pathology to account for iron deficiency overall, supporting the need to perform baseline endoscopy in patients with iron deficiency.